Hi, I'll start off saying new forum user, novice drone user, etc.; using DJI Fly with Mini 2 and Samsung S20 5g Ultra. Appears I have all latest firmware/software updates, etc
From within the DJI Fly app, when you click on album, then select say a photo or video and choose the "share" button, it pops up a mini-menu to select where to share (Facebook, TikTok, etc.) And there's 3 dot to select more share options.

When you hit the 3 dots, it brings up all the share options, not just the 4 or 5 most popular or whatever. Now let's say you select Gmail, my phone pops up an additional menu something to the effect of "you chose Gmail. Do you want this just once, or always?" If you select just once, then it'll share to Gmail then the next time you try to share it'll prompt you to choose from all the share options...

I inadvertently hit "always". Now, as soon as I hit those three dots, it automatically brings up a new, blank Gmail message with the photo/video added as an attachment.

How do I get back to being able to choose to which platform/ where to share my content?

Did you try deleting and reinstalling the app?