Firebase Database Exception: Class java.sql.Timestamp does not define a no-argument constructor

Question

I have an app that was writing and reading perfectly to and from Firebase. I just added in a timestamp, which is converted from a string (see code below):

        try {
            SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
            Date parsedDate = dateFormat.parse(eventDate);
            Timestamp timestamp1 = new java.sql.Timestamp(parsedDate.getTime());
            timestamp2 = timestamp1;
        } catch(Exception e) {

        }

My problem is that when I try to read from the database, I get the following error:

"com.google.firebase.database.DatabaseException: Class java.sql.Timestamp does not define a no-argument constructor."

This error comes when I try to read the data using a data snapshot. See my code below:

eventRef.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {

                for (DataSnapshot eventSnapshot : dataSnapshot.getChildren()) {
                    Event event = eventSnapshot.getValue(Event.class);
                    events.add(event);
                }
                adapter.notifyDataSetChanged();
            }

The error appears to be at the following line in this code:

Event event = eventSnapshot.getValue(Event.class);

Does anyone know how to solve this?

UPDATE: Code for my event class below:

import java.sql.Timestamp;

public class Event {

    public String id;
    public String name;
    public String society;
    public String date;
    public String time;
    public String location;
    public String details;
    public String nameLower;
    public Timestamp timestamp;

    public Event() {

    }

    //required default constructor
    public Event(String id, String name, String society, String date, String time, String location, String details, String nameLower, Timestamp timestamp) {
        this.id = id;
        this.name = name;
        this.society = society;
        this.date = date;
        this.time = time;
        this.location = location;
        this.details = details;
        this.nameLower = nameLower;
        this.timestamp = timestamp;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSociety() {
        return society;
    }

    public void setSociety(String society) {
        this.society = society;
    }

    public String getDate() {
        return date;
    }

    public void setDate(String date) {
        this.date = date;
    }

    public String getTime() {
        return time;
    }

    public void setTime(String time) {
        this.time = time;
    }

    public String getLocation() {
        return location;
    }

    public void setLocation(String location) {
        this.location = location;
    }

    public String getDetails() {
        return details;
    }

    public void setDetails(String details) {
        this.details = details;
    }

    public String getNameLower() {
        return nameLower;
    }

    public void setNameLower(String nameLower) {
        this.nameLower = nameLower;
    }

    public Timestamp getTimestamp() {
        return timestamp;
    }

    public void setTimestamp(Timestamp timestamp) {
        this.timestamp = timestamp;
    }
}