Annoying way I've caught myself between Ryanair and agent. I didn't want to book layover flights myself (painful using Ryanair website) so I've used one of the agent sites.

If you wanna do online checking you need to login using email and not PNR+last_name like most sites. Of course agent used their email and flight was early enough that agent wasn't reachable by phone when my flight commenced. I had to pay 6x20 euro fee at airport for printing a boarding pass, which is a dark pattern by itself.