iTunesConnect: cannot transfer app because of “You must turn off TestFlight beta testing for the app that you want to transfer”

Question

Below you can see that testing for external testers are turned off:

same for internal testing:

but when I transfer app, one of the criterias are not me

Answer 1

For me it was localised test descriptions. Make sure you check that drop down list on the right and clear out info for all languages.