ignorance on the part of the seller

Hey!
I want to complain about this seller alexwourn
I want to tell you that I contacted the seller for the functionality of the code he told me that the code is in good condition, after use I noticed that the code request for a message named “login please”.
the seller has fixed his problem by unlocking it from his server.
after 10 days we added changes to the code which cost us more than $150. after a week the code is locked again which causes us breaks in our work.
after this problem I tried to contact the seller he told me that his family is sick. which is no longer professional. Now I want to tell you that the reputation of the seller is low. he doesn’t even want to solve the problem. as well as he asks me for my confidential work