- A new version (v0.18.0) of the Lemmy server was released a couple of days ago, and it changes the API used by apps significantly.
- Your account is on the lemmy.world instance, which hasn't upgraded yet because the new version is missing an important bot-acount-signup defense feature that is gonna get re-added in a Lemmy patch-release soon. So it's still running v0.17.
- A new version of Jerboa was released (v0.35) with compatibility for the new version of Lemmy.
If Jerboa is working ok for you, you can ignore the error. It will fix itself "real soon now" when lemmy.world upgrades. If Jerboa is broken you can uninstall it and reinstall v0.34 from https://f-droid.org/en/, https://github.com/ImranR98/Obtainium, or direct from Jerboa's GitHub. All of these are a little more complicated than installing from the play store, but not too bad. If you downgrade, be prepared for the opposite message to come soon and you'll want to upgrade again.
If Jerboa is working ok, I suggest you wait it out.