Amex transactions disappearing

Issue: 7 days ago I added my new Amex account to Monzo. I have made a couple of transactions, each of which has appeared in the feed, but some of the earlier few remained in pending despite being processed when checking in the Amex app. When clicking on a pending item, and then going back, the item is deleted from the feed - though the account balance remains correct. Restarting the app does not bring these rows back.

Details to reproduce: Link a new Amex account; make some purchases with the Amex; wait for an item in the feed to get stuck as pending despite being processed in Amex (bug1); click the item in the feed; click back; observe item no longer in feed (bug2).
Device: iPhone 11 Pro
App Version: 4.10.0 #787