C++ 不存在从“std::vector<char,std::allocator<char>>" 到char* 的适当转换函数/E0413/C2664

我想把一个字符串vector数组转化为char型vector二维数组，在倒数第二行会出现如题目上说的问题

#include<iostream>
#include<vector>
#include<string>
using namespace std;

int main() {
    int n;
    cin >> n;
    vector<string>arr(n);
    for (int i = 0; i < n; i++) {
        cin >> arr[i];
        string::iterator it;
        for (it = arr[i].begin(); it != arr[i].end(); it++)
        {
            if (*it == '-')
            {
                arr[i].erase(it); //STL erase函数
                it--;
            }
        }
    }
    vector<vector<char>>arr1(n,vector<char>(7));
    for (int i = 0; i < n; i++) {
        //arr1[i].data = arr[i];
        strcpy(**arr**1[i], arr[i].c_str());
    }

strcpy(**arr**1[i], arr[i].c_str());
->
arr1[i] = arr[i];