Welcome to the forum, I see it is your 1st post.
Who is the manufacturer of your PVC roof?
What are you referring to as sealer? (a coating for the roof or sealant for the seams?)
Most recommendations for PVC and TPO are to clean only with something like Dawn or Spic-N-Span and no treatment afterwards is necessary or recommended.
Sealing the seams with sealant is different.