Turn up like a bad penny
Definition 1 of 1
Pro Tip 1/3Negative Connotation
Implies annoyance or frustration due to someone repeatedly showing up where they're not wanted. 
Just when we thought we'd seen the last of him, he turned up like a bad penny at the reunion.
Pro Tip 2/3Informal Usage
Used in casual conversation, typically not in formal or written contexts. 
At every club meeting, she turns up like a bad penny, much to everyone's dismay.
Pro Tip 3/3Unexpectedness
Highlights the surprise element when someone or something unwelcome reoccurs. 
I paid off my debt, but the collector keeps turning up like a bad penny.