Ubuntu and PHP > 7.1

I'm trying to confirm a suspicion. I'm running a couple of server on Vultr one of them has Ubuntu 17.10, i see on the site that this version (17.XX) is no longer available. You can still get 16 or 18 or 19. I need to update PHP to more than 7.20 and i'm having a very difficult time, the system keeps telling me that could not find 7.2 (nor 7.3 when i tried to upgrade to that one). I'm suspecting that there is no version better than 7.1 for that flavor of Ubuntu. Is that correct? https://19216811.cam/ https://1921681001.id/