No, that's not weird. Your picture explains it all.
This is the lineage recovery, not the TWRP. It might work, but I never tested it. So I guess now you tested it

Please flash the TWRP.
If you don't see something like that:
View attachment 5435123
the lineage recovery is installed. The image above shows how TWRP looks like.
The reason for that is (most likely) that you enabled an option that updates/installs the lineage recovery (effectively replacing the TWRP) with every OTA update. This is (in our case) unwanted behaviour.
So the way to go now would be:
- Disable this option (somewhere under developer options I think. Maybe @MSe1969 could jump in here. Else I'll have another look in the evening.)
- Flash the TWRP
- Verify it is the TWRP
- Check updating again