Just had the same experience. I test and review cameras and have updated dozens. But ThiEYE t5e I haven't updated for fear of bricking, but took a chance with the Edge. Followed the install in camera option. The instructions say if it displays FW ISP 'for a long time' (What is a long time? ) It did display FW ISP. Left it ten minutes. Dead camera like Kleio. Fortunately (sweating a bit) I installed the icatch programme OK. (I'm on Windows 10 and it doesn't always play ball.) Followed instructions AND WOWEE, it installed. Camera is alive again. 1080 was rubbish on the Edge. (I reviewed it.) Let's hope it's better now.
edit : just tested. Still not great at 1080. 4K looks good. I have tested a few budget native 4K cameras lately with good 4K but rubbish 1080. I'd rather have good useable 1080 60 personally. Why the mad rush to compete in the 4K market?
I'm very computer literate but the average Joe in't going to like messing around like this.
ThiEYE make pretty good cameras, but I wish they'd get their firmware dept working properly. Never have these issues with the likes of SJCam etc.