Stopwatch only shows on my iPhone 13 lock screen post iOS 18.1.1 update

Hello

I have an iPhone 13 software version iOS 18.1.1.

I use my stopwatch throughout the day mainly for medical reasons. I start the stopwatch in the app and it shows the current elapsed time only on the lockscreen and the app shows zero. Why? I searched it online and saw that this was an issue from someone back in 2020......

Thank you in advance

[Re-Titled by Moderator]