Just one of (very detailed) maps has this error - - Error 403 nginx/1.18.0 (Ubuntu) - - and is only showing a tiny percentage of my work
This is the one with the error Richard Howe - UK Marked Map - uMap
Whilst the others are all fine and can be edited - Here is one: Germany - uMap
At the end of the day only the people that run umap.openstreetmap.fr can tell you what the problem is or do anything to fix it so you likely need to contact them.