how can i get intouch with a live chat or phone call with someone from Yahoo to

answer my mail questions? I am a paying customer and I am having email problems. these just started with no changes to setting on my end. Please assume I am a very knowledgeable user and have tried all the settings and other things.

Also on my accounts page I am trying to update my address and it won't let me. Every time I try to change it I get an error message back stating that number is already in the system. ( I am not trying to change my number)