No you didn't do it that way. Lemme edit your code and send you. Maybe now you can understand your mistake. <3

#include<bits/stdc++.h>
using namespace std;

#define int long long


int32_t main(){
    ios::sync_with_stdio(false); cin.tie(0);cout.tie(0);
    int n;
    cin>>n;
    string s,ans;cin>>s;
    map<char,int> mp;
    for(int i=0;i<(int)s.length();i++){
        mp[s[i]]++;
    }
    bool t = true;
    for(auto it: mp){
    	if(it.second%n!=0){
    		t=false;
    		break;
    	}
    }
    if(!t)
    cout<<-1<<endl;
    else{
    	int m = n;
    	while(m--){
    		for(auto it: mp){
    			int z = it.second/n;
    			for(int i=0; i<z; i++)
    			cout<<it.first;
    		}
    	}
    	cout<<endl;
    }
}