Where is the problem in the code

this is code oK

Code:

-(IBAction)callPhone:(id)sender {
    [[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"tel:2135554321"]];
}

but , I want to use "*" or "#"

As in the example

Code:

:@"tel:*188"2135554321#"]];

I read:
"
To prevent users from maliciously redirecting phone calls or changing the behavior of a phone or account, the Phone application supports most, but not all, of the special characters in the tel scheme. Specifically, if a URL contains the * or # characters
"

How can I use "*" or "#"?
Contact request


Good day,