I'm trying to use the regenerateChunk method, but I get an error message Caused by: java.lang.UnsupportedOperationException: Not supported in this Minecraft version! Unless you can fix it, this is not a bug.
is there another possibility to reset a chunk
If you play on the Java, you can use the NBT-Explorer program to open the level.dat of your world, then you have to find out which file is the file of the chunk and then delete it. Unfortunately I don't know from my head where the data of the chunks are, but there should be instructions on the Internet…
If you play on the Bedrock… I don't know.