After I updated Minecraft to 1.19.30, I went to join my Realm after it updated, and I spawned in my house as usual, but my map was different. It appeared black on multiple maps in the shape of a circle. When I moved around on the Realm, it would create more black circles on the maps. I then tried to fix it, and it did work, but after logging off and joining again, it would glitch the maps even after I fixed them. Basically, how to recreate the issue, is log on to your realm on 1.19.30, and if you have maps, they should just black out in the form of a circle. I hope this gets fixed, and thanks for taking the time to solve these problems.