Authentication Timeout on External Bank Account Connection

Issue: When I attempt to connect my HSBC student credit card to Monzo using my plus account I get an error saying authentication had timed out when I get sent back to Monzo from the HSBC application (HSBC appears to authenticate on their end).

The same issue happens when attempting to use the Monzo app to transfer money from my connected Halifax account (after being redirected back to the Monzo app), yet again it authenticates fine on the Halifax side.

Details to reproduce:
OS: iOS 16.1.2
Device: iPhone 14 Pro
App Version: 5.5.0

Screenshots: