My girlfriend still has ex's phone number in her phone saved under name "B" (first letter of his name). Should I be worried?

My girlfriend still has ex's phone number in her phone saved under name "B" (first letter of his name). Should I be worried? I found that out today by accident when she sent me a screenshot. She did tell me she had him saved under that before we met and that also she never talks to him.
My girlfriend still has ex's phone number in her phone saved under name "B" (first letter of his name). Should I be worried?
Post Opinion