Make sure you check which instance you are on. Jerboa will show you lemmy.ml by default (I think?) While other apps probably show lemmy.world by default . Make sure you set the instance to where you actually registered your account.
I like the app a lot, but I have issues reading the font, which is the main reason I use Jerboa. Had the same issue with Voyager, but they implemented the ability to switch font styles from IOS to Android. Any chance to see a similar option in Thunder in the future?