Have I found a glitch in ID Safe?

Re: Xfinity Norton Security Suite, Version: 22.7.1.32

I think I may have found a glitch in my Norton Security Suite ID Safe.

I have an account at https://xyz.force.com. (XYZ if fictitious here, but the real account ends with force.com)
I also have an account at https://xyz2.force.com. (XYZ2 is fictitious too, but really ends with force.com)

Each of the URLs is for a totally different company, but happen to end with force.com.

Both of the above accounts use the same email address as Username and different passwords.

Norton ID safe will only let me save the account login credentials for both accounts if each has a different email address as a Username. If both of these accounts use the same email address as the Username login, ID Safe will only let me save one or the other, but never both.

After days or trying to save both accounts in ID Safe, I realized that if I use a different email address for each, then it works fine.

My thinking is that the glitch might be related to the fact that both of these URLs end with force.com.

I can recreate the problem again and again and fix it by using different email addresses.

Any ideas why would this be happening and if it merits a fix?