You need Kelly Corruption 100 on Level 2 first to buy the second swimsuit. For Reaching Level 2 Corruption you need to finish her personal event "No panties library flashing."
You could try a restart or an older save. I played 2 times on win version and don´t got stucked. My tip for a new play is to go not so fast on corruption. Corruption increases so fast only by events, no need to boost that more at home with tools or porn. Perhaps there is also a problem when you go to fast on corruption? There is also the possibilty that steve library scene 2 is before scene 1, depending on your answer on viki. This could also be a reason to trigger your stucking? Could be also wise, to wait for next update first.