Strange behavior - App suddenly producing ANR

Question

I know it sounds strange/ridiculous, but I am having this issue

Update#2

I am sharing the code that is indicated by @EpicPandaForce.

SyncService.onNetworkSuccess

public void onNetworkCallSuccess(Response response) {
    List<TransactionHistory> historyList = (List<TransactionHistory>) response.body();
    if(historyList != null && historyList.size() > 0) {
        TransactionHistory max = Collections.max(historyList, new Comparator<TransactionHistory>() {
            @Override
            public int compare(TransactionHistory o1, TransactionHistory o2) {
                return o1.getUpdatedAt().compareTo(o2.getUpdatedAt());
            }
        });

        if(max != null) {
            session.putStringForKey(Session.timeStamp, String.valueOf(max.getUpdatedAt()));
        }
        for(TransactionHistory history : historyList) {
            String id;
            if(history.getTo().equals(history.getFrom()) ||
                    history.getFrom().equals(session.getStringForKey(Session.fpIdKey)))
                id = history.getTo();
            else id = history.getFrom();


            LatestTransactionResponse latestTransactionResponse = new LatestTransactionResponse();
            DateTransactionResponse dateTransactionResponse = new DateTransactionResponse(DateUtility.getDateFromEpoch(history.getEpoch()));

            dateTransactionResponse.addTransaction(history);
            latestTransactionResponse.setArchived(history.isArchived());
            latestTransactionResponse.addTransaction(history);
            latestTransactionResponse.setId(id);
            dateTransactionResponse.setId(id);
            LatestTransactionRepository.getInstance().addLatestTransaction(realm,
                    latestTransactionResponse);
            ContactTransactionRepository.getInstance().addNewTransaction(realm, dateTransactionResponse, id);
        }

        try {
            Activity temp = MyFirebaseMessagingService.getRunningActivity();
            if(temp != null) {
                if(temp instanceof MainActivity) {
                    ((MainActivity) temp).refreshLatestTransactions();

                } else if(temp instanceof TransactionDetailActivity) {
                    ((TransactionDetailActivity) temp).refreshOnMainThread();
                }
            }

        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}

addNewTransaction

public void addNewTransaction(Realm realm, final DateTransactionResponse response, final String id) {
    realm.executeTransaction(new Realm.Transaction() {
        @Override
        public void execute(Realm realm) {
            List<TransactionHistory> tempHistoryList;
            DateTransactionResponse temp = realm
                    .where(DateTransactionResponse.class)
                    .equalTo("id", id)
                    .equalTo("date", response.getDate())
                    .findFirst();

            if(temp == null)
                realm.insertOrUpdate(response);
            else {
                tempHistoryList = temp.getTransactions();

                for(TransactionHistory history : response.getTransactions()) {
                    boolean found = false;
                    for(int i=0; i < tempHistoryList.size(); i++) {
                        if (history.getId().equals(tempHistoryList.get(i).getId())) {
                            if(history.getStatus().equals(tempHistoryList.get(i).getStatus())) {
                                found = true;
                                break;
                            } else {
                                tempHistoryList.get(i).setStatus(history.getStatus());
                            }
                        }
                    }
                    if(!found)
                        tempHistoryList.add(history);
                }

                //realm.insertOrUpdate(temp);
                realm.copyToRealm(temp);

                //DateTransactionResponse transactionResponse = temp;
                //temp.deleteFromRealm();
                //realm.insertOrUpdate(temp);
            }
        }
    });
    //removeDuplicateTransactions(realm);
}

removeDuplicateTransaction

private void removeDuplicateTransactions(Realm realm) {
    realm.executeTransaction(new Realm.Transaction() {
        @Override
        public void execute(Realm realm) {
            RealmQuery<DateTransactionResponse> query = realm.where(DateTransactionResponse.class);
            RealmResults<DateTransactionResponse> results = query.findAll();
            List<DateTransactionResponse> transactions = new ArrayList<>(results);
            for(DateTransactionResponse response : transactions) {
                List<TransactionHistory> historyList = response.getTransactions();
                Set<TransactionHistory> historySet = new LinkedHashSet<>(historyList);

                RealmList<TransactionHistory> histories = new RealmList<>();
                histories.addAll(new ArrayList<>(historySet));

                response.setTransactions(histories);

                realm.copyToRealm(response);
            }

        }
    });

}

Update#1

There are 3 tabs with RecyclerViews on my main screen. Below are the implementation of Adapter for all three.

I have been developing an App for quite a time. It has been working just fine and I occasionally work to improve its performance. It is still under development. Some days ago, I cut-out the branch and done nothing notable (just one or two bug fixes) and started testing it and OOPS it started giving ANR's. I revert back to previous branch and very strangely it started giving me the same result. I have removed all changes and tried, still the same result. I am not sure what's happening. I tried to study traces.txt, but couldn't find waiting to lock as suggested in this SO answer.

I have also difficulty reading traces, couldn't find the culprit. Here is the traces.txt file.

I am using Realm as Database in my application and couldn't find a way to perform operations on Realm on other thread. I tried to find any other culprit in code, but all is till the same as before which was working perfectly fine.

Hierarchy

Here is the App Hierarchy.

Login screen is shown and user enters PIN. Then comes the main screen. Main screen contains 4 tabs, just like WhatsApp i.e first tab is camera and rest contains RecyclerViews in which data is being populated from Realm. ANR is only happening here. Keeping in mind that it was literally perfect some days ago until I took branch out and fixed some bugs, which were not even related to the main screen.

Any help or direction is highly appreciated.