Unable to see any cards to select in Lovelace

When editing a dashboard, and selecting ‘Add Card’ no card options are available to select. I have tried this in both Safari and Chrome and cleared caches in both, and restarted HA along with reloaded themes.
I only see the below:

This is only happening with one dashboard which was working fine yesterday.

Does anyone have any ideas what could be causing this?

Figured out it was because there was an error in a card on a separate tab view