There are three ways to reach Roblox. You can call their customer support line at 844-200-2490 and leave a voicemail to receive a call back, fill out their online support form for general issues, or email their customer support directly to ask specific questions. You can visit the Roblox support page at https://www.roblox.com/support.
Source: https://community.expensify.com/discussion/32485/how-can-i-talk-to-roblox-a-real-person-support/