Hi Ali. Many thanks for the update. All good now. Cheers.
I also cannot log in to our WP Ulike account as wpulike.com is returning an “Invalid SSL certificate” error via Cloudflare.
A quick note in case this helps anyone else. I managed to fix the problem using the “Regenerate Thumbnails” plugin. Still not sure why it happened after the upgrade, but a couple of hours later and all is well again.