Poshmark Did not correct website glitch Redwood City California

I made a sell of my cookbook, Chrissy Teigen Teaches Your Child To Cook, which is also at Lulu bookstore distribution. I needed to verify my account and phone number with Poshmark online, so I could download shipping label to mail customer their cookbook. 

There's a glitch on the Poshmark website preventing me from updating and verifying my information. I reported it to Poshmark that never fixed the problem. The customer never received their cookbook. It makes me look untrustworthy. I also lost a sale.