Migrating to thunkable

hello
i am migrating from ai2 mit appinventor to thunkable, i uploaded my aia file and the keystore but when packaging app it gives an error “Error generating Yail for screen 5658738206179328_Screen1: : Cannot read property ‘0’ of undefined. Please fix and try packaging again.”
in addition to that thunkable live is not showing my buttons and labels clearly