Sr. Citizen Level Problem: No eMails Working ?

Hello,

Sr. Citizen now, very,  and would appreciate any help with this.

Going to the Comcast store in Framingham MA, again, is a real problem for me these days.

This happened, also, several months ago.

Should have taken notes !  They were able to get it working again in a few minutes.

So,

Today, my emails on my iPhone, and also on my mac computer stopped working.

Cannot send or receive on either.

Internet, etc. works fine.  XFinity on their site says no problems in my area.

Any suggestions as to what might have happened, or what I should check would be

most appreciated.  Not too likely that I changed anything inadvertently, as it worked fine in early am,

and then a few hours later wouldn't.

Most  likely problem on my end, but of course the possibility that it is something on theirs exists too.

What should I check, etc. ?

BTW: is this something I might be able to work with a human at Comcast

over the phone with ? Practical ?  

If so, do you have a phone number for; I have problems navigating their site(s).

Would much prefer, though, trying out suggestions from you folks.

Thank you very much, much appreciated,

Bob