Battery verification message after replacement

I know this is an obvious and well-known problem, still I’d like to listen to some input from this community.

I just replaced a client’s iPhone XS battery without doing prior research. If I had known what kind of childish games Apple was playing, I wouldn’t have accepted the job. Client is now complaining about the battery error message that keeps popping up every 10 minutes. He doesn’t care much about the “service” label in battery health. The pop-up is extremely annoying though.

Is the only way to fix this issue to solder parts from the original battery onto the replacement one? If so, I’ll remount his original battery.