Terrain tools don't work

Hello. I’ve been working on a game for a few days now, and earlier today my terrain tool stopped working. All terrain tools except for flatten don’t seem to affect the terrain I’ve made previously. I tried restarting, reinstalling roblox studio, enabling and disabling all beta features and it still doesn’t work. It seems to be a problem only on this account, as I tested it on my alt and it worked normally. Screen recording