> "cant replicate it"

Holy shit, if you were providing a service and sent me (a customer) an email like that I'd leave you in a heartbeat. Talk about a "fuck you".

I get customers can be hard but "can't replicate it" translates directly into "find another service provider".

Really, if the relationship has moved to this level a canned "We're sorry but we are going to have to terminate this relationship, here's a generous timeline and a few freebies to make us look like the better person" response would have been MUCH better.