I have steam up in a web browser, mobile web browser, mobile app, and steam proper. All of these are authorized devices. I'm literally trying to spend $0.26 on some Bloons TD trading cards so I can complete the set and craft a badge.

After clicking purchase, I'm redirected to a page that says I must confirm the purchase on the mobile app. I go into confirmations on mobile and see the transaction that is pending. I indicate that it is me making this purchase, and hit confirm. The transaction disappears from the "confirmations" list, but the original purchase page (as stated, on Steam itself or in a browser) never updates. So it just sits there forever, awaiting my mobile confirmation (which has already been confirmed)

I'm not exactly new to steam, but I'm failing to jump through these hoops. I just want those cards >.<