One signal compiler error


Hello guys, i have a problem about one sign al push. Normaly if i crate a New project there is no problem, i m sending notification very well, but i have a app, i m using ten page, 4.2 mb, i important it from mit app inventor, i added this app fire base Db there is no problem, but when i add one signal, appy builder given compile error, i try lots of thing but dosent working,
Please can you Help me?