This app was mentioned in 1 comment, with an average of 1.00 upvote
Another phone victim to dumb partitioning. My Oppo had to wait for a year until they officially released a patch for the ridiculous 2GB app limit, and your situation seems even worse, since I don't expect them to release a fix officially. My best advice is to watch custom development for the phone closely, maybe some smart modder manages to fix it with LVM or something.
In the meantime you should get an external SD and use an app like this one to move application data to that SD card.