Wrote a C++ code for a leetcode problem, but getting error for 2 sized arrays

Question

class Solution {
    private: 
    int findpiv (vector<int>& nums, int l, int h) {
        if (l > h) {
            return -1;
        }
        if (l == h) {
            return l;
        }
        int mid = (l+h)/2;

        

        if (nums[mid-1] > nums[mid] && mid>l) {
            return mid-1;
        }
        if (nums[mid] > nums[mid+1] && mid<h) {
            return mid;
        }
        if (nums[l] > nums[mid]) {
            return findpiv (nums, l, mid-1);
        }
        return findpiv (nums, mid+1, h);
    }

    int bsearch (vector<int>& nums, int target, int l, int h) {
        if (l > h) {
            return -1;
        }
        int mid = (l+h)/2;
        if (nums[mid] == target) {
            return mid;
        }
        if (nums[mid] > target) {
            return bsearch (nums, target, l, mid-1);
        }
        return bsearch (nums, target, mid+1, h);
    }
public:
    int search(vector<int>& nums, int target) {
        int piv = findpiv (nums, 0, nums.size()-1);
        if (piv == -1) {
            return bsearch (nums, target, 0, nums.size()-1);
        }
        if (target == nums[piv]) {
            return piv;
        }
        if (target >= nums[0]) {
            return bsearch (nums, target, 0, piv);
        }
        return bsearch (nums, target, piv, nums.size()-1);
    }
};

For this question, this is the code I wrote. I'm getting an input array which is rotated and sorted. I first of all find out the pivot point of the array. And this is where I believe the error is arising.
I first felt that nums\[mid-1\] would be giving me an error for mid == 0. But, in that case, l == 0. Hence mid\<l won't satisfy, and it should not give me an error.
Maybe I'm mistaken in my concepts. Hence please guide me.