MuseScore pour Iphone 5SE

Using MuseScore 2.1.9 on my Iphone 5SE : Playing a long score file attached but also included in the 5 scores of "my score", I try to create a loop. All is OK when it concerns the first part of the score but if the loop start near the end of the score it is impossible to create the loop ; the starting point became the last point.
I think it is a bug, pleace check this event.