If you ever had multiple accounts logged into Pachli, and then logged one of them out, Pachli's database may contain orphaned data.
This is now triggering a crash on startup in 2.10.0 (more details at https://github.com/pachli/pachli-android/issues/1320).
If you've already upgraded with no problems you can keep using 2.10.0.
If you haven't upgraded then I've paused the rollout on Google Play and I'm blocking the release on F-Droid.
2.10.1 with a fix for this will be released next week. Sorry for the inconvenience.