The data does not support the premise. Across 96,400 sessions, 82% on phones: only 8.5% left without doing anything at all. Average engaged time 34 seconds, and 65% actively tapped something. That is not a picture of people arriving and bailing. If sales dipped, the leaving is not happening on the way in.
A defect in our own numbers, before you use them:68,300 of those 96,400 sessions list tigerfriday.com itself as the referring source. That usually means single visits are being chopped into several sessions, which would make people look like they leave and return more than they do.
What is real on phones: the site takes 248ms to react to a tap, so it feels ignored and people tap again, 3,320 rage clicks in three days. A small slice gets a genuinely broken page, worst real visitor waiting 50 seconds. And taps that never register at all, 124 on the mobile menu, 22 on Add to Cart.
Do not let anyone sell you that last one as the cause of a revenue problem. It is a few dozen sessions. Also good news: the old hidden-menu-button issue shows zero hits, consistent with a fix.
Harvv says your site’s structure did not change in this window, so if sales moved, the cause is probably not on the site at all. Check stock on the sold-out products, and any price, promo or ad change. Tell me what happened off-site and I can tell you which of the above matters.