Probably as Blighty indicated, you have a filter in force.
I did write a bit about filters and tags some time ago
https://www.gimp-forum.net/Thread-Brushes-and-Tags Not a wonderful read. But the advice at the bottom of that is valid.
Totally screwed up the tags you assigned? Go to your gimp profile and delete the file tags.xml Gimp will create a new default file next start up.
Caught me just as I was closing down for the night. So a very rough video on the subject.
https://youtu.be/l4kf-C7eGq4 duration about 3 and a half minutes
I did write a bit about filters and tags some time ago
https://www.gimp-forum.net/Thread-Brushes-and-Tags Not a wonderful read. But the advice at the bottom of that is valid.
Totally screwed up the tags you assigned? Go to your gimp profile and delete the file tags.xml Gimp will create a new default file next start up.
Caught me just as I was closing down for the night. So a very rough video on the subject.
https://youtu.be/l4kf-C7eGq4 duration about 3 and a half minutes