@mrspock Welcome to the forum!
This appears to me to be a Bitwarden bug that must have cropped up in the past few weeks. I have seen a handful of other similar complaints (here, here, and here), and the common factors appear to be that the operating system is macOS, and the user has set a custom value for the timeout period. Interestingly, these complaints started around March 17, but there were no new Bitwarden client releases between Feb. 17 - March 20. Unless it took one month for the Apple app store to approve the Feb. 15-16 releases (version 2023.2), this observation suggests that an update in the operating system or browser is the underlying cause for the problem (by causing some incompatibility with Bitwarden’s timeout processes).
I don’t believe that this bug has been reported on GitHub yet, but hopefully someone will do it soon and get the developers’ attention. I hesitate to file the report myself, since I don’t use macOS (and therefore cannot provide the detailed information required for a bug report).
Until this gets fixed, you can select the predefined 4-hour option for your timeout period, which should at least give you a little bit of a reprieve.