Editing paypal details on classipress plugin

Hello to all developing team.
I’d like to ask you about help cause I found myself in difficult situation. I got as a heritage from previous employee site to work on and I have very small in common with it. The classipress plugin was bought in here from themeforest and source is here: ogloszenia.miastoiludzie.pl.

When you add an advert you can disticnt it on the site and this is paid option by paypal. Our paypal detail are changed now and there is no option to edit any details about paypal account on the wp-admin gateways site.Does anyone know how to deal with it? Is there any option to edit database or something similar?

My best regards