Can't activate Voxi SIM using Monzo Flex due to X-Frame-Options

Issue: I was unable to activate a Voxi SIM using Monzo Flex; after submitting the card details, the iframe fails to load. The JS console shows the error:

Refused to display ‘https://verify.monzo.com/’ in a frame because it set ‘X-Frame-Options’ to ‘sameorigin’.

Details to reproduce: Activate a Voxi SIM at https://www.voxi.co.uk/activate/activate-free-sim on desktop, choose a plan and and use a Monzo Flex card to check out. After submitting the card details the iframe fails to load.

OS: MacOS 26.4.1
Device: Macbook Air
App Version: Chrome 148.0.7778.216 (and Monzo app version 7.29.0 #7290051, but that doesn’t seem relevant)

Screenshots: (sorry, closed it now)

Have you tried another web browser?

This isn’t a Monzo issue.