Contact form not working

Hi, I’ve been trying to figure out how to solve the issue that I’m having for a couple of days now…
At first, I’m having an error when submitting the form which is “There was an error trying to send your message. Please try again later.”
I’ve tried also using another mail server, which is WP Mail SMTP.. test email is working but going through with the form, still gives the same error. I’ve tried searching on forums on your plugin, found the same issue and you’ve answered with this link “https://contactform7.com/faq/i-get-an-error-message-with-a-red-border-so-how-can-i-solve-this/”
So I’ve tried contacting the host for support… We’ve been trying to find what causes the issue but it is not from their server.
Now, trying out the form doesn’t give me an error but still, it’s not working.. It just shows a loading icon on the side of the button, continuous loading icon.. that’s it.

Can anybody help me? This is the best and most flexible plugin for contact form, I don’t want to give it up.

PS. I’ve been using this plugin for years now. On different websites that I’ve developed and on the same host. Everything’s working great on the other but not on this one.. I don’t know how or what happened.

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