Hisense Android TV and Tivimate USB recording

I have a Hisense U8G TV and have installed Tivimate on it. I also have Tivimate installed on a Firestick 4K Max attached to the TV.

However, I'd like to be able to use the TV exclusively for IPTV but can't seem to get the system to recognize my USB stick (I've tried several). I've formatted them on my PC (FAT32) and plugged them in as well as formatted them on the TV as removable storage. I can read their contents with a file manager, but that's about it. However, Tivimate gives me a "failed to change directory" error when trying to save the recording directory.

Am I just out of luck? I can continue to use the Firestick as my IPTV system; I just thought it would be nice to consolidate everything into one device.

Thanks in advance.