Form stopped sending - super frustrating

I’ve set up two forms on my website which worked…at first. Then they stopped working. It appears the fix is to switch my php on my host from 7.3 to 7.4, back to 7.3 and clear the cache.

In the meantime I’ve lost a load of form submissions. I’m sure there’s an explanation but I’m at a loss to figure it out.

Here’s the website:

In my experience the exact server setup is unlikely to be the cause. What might be happening when you change php version is your host switches you to a different server, with a different IP address, which has different reputation.

Anyway the best way to troubleshoot this is to use grab a temporary email address there, plug it in your recipient field in Sparkle (form button settings), publish the site, send a contact form, then go back to to check the score. That generally contains indications on what’s wrong.