There is 80 MB allotted to the tile cache storage and it sounds like if you use it all the time it might be full.
We have a way to delete all the cached data in there already. Press and hold the button that changes the basemap style. This will show a message that says "The Mapbox annotations have been reloaded. It can take a while for the changes in Mapbox to show up here."
Testing in Airplane Mode for any important job is also a good idea.