Insta360 Go 2, 64GB, SD card too slow error

My recently purchased the go 2 is experiencing the following problem:

Whenever I shot pro-video, a “SD-card too slow” error would appear after 3:30~5:00 minutes, shooting would stop. I now can hardly shoot any video longer than 3:30.

From researching the forum, it appears that SD cards in an Insta360 needs to be hard formatted once in a while. However, the GO2 uses internal memory with about 8GB of system file also stored. Is there a way to fix this issue?

Thanks in advance for your help!

Best regards

Horace