You have to become a normal vampire and then cure the condition. Serana can turn you if you've completed the Dawnguard questline. You can also fight vampires until they infect you.
I think the OP's problem is that Serana drank the potion and became a vampire, presumably after he/she had her cured. Serana's cure dialogue only shows up once so she might be stuck as a vampire for good this time. There are probably mods to fix it but whether they're available on PS4 is another matter.