The hosting company had a problem with their servers.
After a few days they contacted me and said all was sorted. Which it wasn't.
They come out with the usual have 'you' tried this have 'you' tried that.
I finally messaged them again last night and had a bit of a rant. I'd tried everything !!
They contacted me this morning.
I have checked your situation and after reactivating the SSL certificate the website is working like a charm 😊
I didn't deactivate, and can't activate, that security certificate myself. They control it, I just pay for it