How to restore tabs' groups.

I've been using "tab groups" for a while but then suddenly my tabs' groups that I just had saved just disappeared, when I had a lot of them of my pending activities. I don't know why it happens, please help me to figure that out cause I had a lot of information that I didn't save on bookmarks. Like I just showed in the uploaded image, I just could restore 1 group tabs because my firefox and laptop turned off and I had that group open before it turned off, so firefox notified me that there was an error and I cannot have all my information again, but at least let me restore my last session, that why I could recover One TAB GROUP