Weird characters being displayed before results in console.

This is basically what the problem looks like (the characters aren't actual equal signs, but similar):

Enter string to reverse: AMAZING
Reversed string: ===============GNIZAMA
Do you want to insert another string (Y/N)?: Y

Enter string to reverse: NEVER
Reversed string: ====================REVENMA
Do you want to insert another string (Y/N)?: N


Here is my code:

#include <iostream>
#include <string.h>
using namespace std;
  
void Reverse(char *str);

int main()
{
	char user_input[40];  
	char new_input[40]; 
    char next_item;

    do
    {
    cout << "Enter string to reverse: ";
	cin.getline(user_input, 40);
	Reverse(user_input);
    cout << "Reversed String: " << new_input << endl;
    cout << "Do you want to insert another string (Y/N)? ";
	cin >> next_item;
	cin.ignore();
        
    }

    while (next_item == 'Y' || next_item == 'y');
	

return 0;
}

void Reverse(char *str)  
{                 
	int x = strlen(str);
    for(int y = x; y >= (x/2)+1; y--)
    {
  swap(str[x-y],str[y-1]);
    }


}