I've been using the Peak Design clip with both the X-T2 and the X-T5. Works really well - very reliable and holds the camera steady. Just upgraded to the most recent version (more slimline), which is just as good. Solid and well made.

So this isn’t a new camera from a FujiFilm dealer? I’m guessing that from the comment about the third party battery. I would go back to the seller.

Hi! I've just purchased an X-T5, which is a good chunk bigger and heavier than my previous cameras- So I'm interested in alternate ways of carrying it other than a strap. Peak Design's capture clip (or similar alternatives) come to mind and seem to be exactly what I need. But I'm concerned about the long term safety of mounting a camera like the XT5, maybe with a not super light or small lens (like the 16-55 2.8), considering that a tripod mount was not inherently designed to be holding weight in that way. Has anybody been using these kinds of mounts? How's it been?

I have the proper sandisk SDXC v30 card that's used for 4k. the battery is fully charged.  however - 1. I updated the firmware but it's still the same.  2. the battery that the sellers sent is actually third party. it's by a company called batmax. I'm wondering if that is the cause.  3. the high speed recording mode is also greyed out so turning it off is also not an option. 

Do you mean that the camera completely powers off when you start to record a video? Not sure why it would do that unless there is a fault but if the setting to change Movie Mode is greyed out you might have the High Speed Recording Mode turned on - at least try turning that off but it shouldn't power off the camera. There is always a chance its a card problem - do you have a different card you could try? Is the battery fully charged?