Xbox Elite Series 2 - Problem can't contact Microsoft to fix. What to do please?

The left button does not work correctly. Has been difficult since I bought it and now it's finally going bad and not working properly. It's only 7 months old and still under warranty. I went thru the process online to get it sent and fix but the very last screen says that something went wrong and need to contact us. Whenever I try to contact us, there is no number anywhere or chat box. So how would I go about getting this $175.00 controller fixed? Or do I have to spend another $175.00, or more, after only 7 months of use, and the button has never really been right from the beginning, and is getting much worse.

Thank you if anyone can help before the warranty expires.

:)