Vox email sucks

Since I have been with Vox I had excellent service besides my email box. I get delays of hours before people get my emails and visa versa. They seem unable to find the real problem and some of them told me it is the settings others it is the other person's exchange, while others blame the algorithm that checks for profanity. Well, I had it wkthem and am looking for an ISP that can ensure my communications are taken care of as a matter of priority.