So much for a reputable brand

Buying online in this day and age should be the easiest thing to do... oh no not with Nike. Since Thursday I’ve been trying to buy something online after I received an email from Nike telling me it’s available. I’ve been struggling for 2 days. I’ve now successfully got to the check out page and I receive an error all the time. The contact center number doesn’t work. I called a branch, they can’t help me. I need to make this purchase ASAP before I lose the size I’m looking for. Who else can I call? Who can help me?