(iOS) Lightroom mobile Help with Masking

Hi! I am trying to add a Mask to my photo but having real issues trying to apply it 🫠

I have edited my photo in Lightroom Mobile on iOS and added a mask in the Maaking area, but when I click the tick in the bottom to apply it, it leaves the masking edit area and returns to the main edit screen without making the changes. I want to save my photo to my device with the masking changes but it won't let me and I have no idea how to do it - would someone be able to help advise on the right way?

thank you!

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