@Naji49
Oh no, what a mess. I hope you get this sorted and don't have to leave or at least get your money back.
All this was unavoidable. You simply needed to send a date alteration request to your host or he could have sent one to you. The cost of the stay is then automatically recalculated, the other party accepts the request, job done.
I am surprised the host didn't just do that as there was no need to contact CS. Is he inexperienced?