Strugling to make a mask work on a text object with fx?

I have a row of 'tabs' that are text objects with some effects on them. I cant for the life of me work out how to apply an image mask to them?

When I create the mask it just applies to the text - not the shape?

Cant seem to upload the .ai file so its here on dropbox: https://www.dropbox.com/scl/fi/hzf96hzufxe60vbalmu2k/Mask.ai?rlkey=ykps5g09oouuq7j3sugnxdgcc&dl=0

Image below of what I want to achieve! Thanks in advance!!!!