Name Block in Gmail Signature Randomly Changed

I have a very strange issue. I have seen it three times on user gmail accounts (yes, we use Gmail for business). I have Googled it and searched, but not found any explanation or even other occurrences.

The first time, a user named "Patty" sent an email to her boss. When he received it, her name had been changed to "PUMP." Anytime he tried to look her up in his contacts, or read other emails from her, or even send an email to her, it would change her name to "PUMP." Signing out of all Gmail sessions, changing the password and clearing the browser cache fixed the error.

The second time, I can't recall the person's name, but it was a repeat of the first name changing and being replaced with a random word. Again, signing out of all Gmail sessions, changing the password, and clearing the browser cache fixed the error.

Today was the third occurrence. This time, the user's name was changed to mimic a racial slur. (One letter was off, so that it would only sound like the word if the name was read aloud.) The fix was repeated and the error corrected, however, we are curious to know if anyone else has seen such a thing or knows the cause of it.