Layer mask keeps resetting when working in timeline editor

[#1]

I'm making a short 10 second video where one part of a still image moves while the rest stays still and to achieve the effect I have to mask some parts of the image out. For some reason after I paint the mask on and make the key frames, if I pause the video or click on the mask again to make edits, the entire thing turns white, making the effect invisible. I can backspace to bring the painted mask back, but even locking the layer doesn't prevent it from changing in the first place. In order to export the video with the mask I end up having to backspace and export it without being able to preview the final video. Though I can easily repaint the mask to make the effect again if I need to, it becomes tedious having to constantly redo the mask every time I want to preview the video or edit a small part of it, especially if I forget that it has changed and I can no longer easily backspace to get the mask back. Is this a glitch or something related to user error? I am working on a 2017 Macbook Pro and using an external hard drive to store my apps. I'm also using the most recent version of photoshop. Answers are greatly appreciated!

[kevin stohlmeyer]

Hi @ is this the same image layer? If so, you can't edit the layer mask on the same image in frame animation which is why its resetting.

You'll need to have a separate image layer and mask for each frame that you can independently edit the mask as needed.

[#3]

I might be a little confused about what you're asking, but the mask is its own layer. Everything in group 1 is what has been animated and mask is its own separate layer made from the original image. The only key frames associated with the mask are for the size because the video slowly zooms in throughout the duration, but the mask itself is not animated.

[kevin stohlmeyer]

Hi @ you cant edit the same mask over and over in animation frames. You need a separate mask for each frame.