API version warnings in admin area

When editing pages in the admin area, there are console warnings for every block as follows –

deprecated.min.js?ver=990e85f234fee8f7d446:1 Block with API version 2 or lower is deprecated since version 6.9. 
See: https://developer.wordpress.org/block-editor/reference-guides/block-api/block-api-versions/block-migration-for-iframe-editor-compatibility/ 
Note: The block "nhsblocks/nhstabs" is registered with API version 2. 
This means that the post editor may work as a non-iframe editor. 
Since all editors are planned to work as iframes in the future, set the apiVersion field to 3 and test the block inside the iframe editor.

nhsl-block-editor-styles-css was added to the iframe incorrectly. 
Please use block.json or enqueue_block_assets to add styles to the iframe.

I have WordPress v7.0 / Nightingale theme, and all my other plugins are deactivated apart from Nightingale companion.

No errors or warnings on frontend.