Thanks for the report, no problem! This issue has been seen by other players, and it's a bug with the current version of GZDoom: https://itch.io/post/663685
GZDoom's developers fixed the bug, but I'm not sure when a new build of it with that fix will be out. In the meantime, if you don't need features from the very latest GZDoom you could try using an older build of it from the 3.6 series.