It now "belongs" to the ex-roomate. Ask that person to remove it.
The ownership of Apple equipment with an activation lock is demonstrated by access to the Apple Account that is signed into the device, by accepted documentation (e.g., a receipt from an Apple authorized reseller), or documented provenance from a deceased owner (in that situation read: How to request access to a deceased family member's Apple account - Apple Support ) Apple can completely reset a device if a person can provide sufficient evidence of valid ownership. This is done online* at: Activation Lock support request - https://al-support.apple.com/#/additional-support Apple says, "Proof of ownership documentation is required," but does not provide many details in the article as to what is acceptable proof. Prior to this official service Apple typically required the original receipt** issued by Apple or an Apple Authorized Reseller and documented provenance (so typically it would be the first owner who does this, or a descendant with legal proof of ownership transfer). Note that while this will let you get use of the device again, it will not help you with lost access to an account.
* There is a special link for this service. To save time you should use it instead of https://getsupport.apple.com/
**Apple recommends you keep your receipt after you buy an Apple device. --> Keep your receipt after you buy an Apple device - Apple Support