Roblox account got hacked and all my robux were spent, what now

once it's secured, ask support about the items specifically. they have been known to restore stolen limiteds or roll an account back, but robux spent in someone else's game is much harder to get back, so don't count on that part. put the date it happened and exactly what's missing in the first message.

if you can still log in, do this right now in this order: change the password, check the email on the account hasn't been swapped for theirs, turn on 2-step verification, then use "log out of all other sessions" in the security settings. after that send a ticket through roblox support explaining it was compromised and give the rough date. I wouldn't count on getting the robux back, but report it anyway. also worth asking yourself how they got in. a "free robux" site, a browser extension, or reusing the same password somewhere else are the usual ones.