connection timed out

i have a VPS XL server through IONOS; it runs on Plesk. I have several wordpress websites on the server. The server has an SSD capacity 160GB and there is over 80GB free. I am using wordpress 6.1.1. All of the software is up to date. At the moment i am concentrating on one of them, w8-loss.com

I have not been able to do much work on my website w8-loss.com because of connection timed out issues. I have full fibre optic running at 100Mb. Every time i tried to amend the website i was getting timed out errors. I am using GeneratePress Premium as my WordPress theme. As i was anxious to get some work done on the site and other sites i started to investigate what was happening. I came across an article on kinsta.com with 12 possibles solutions and i have been working my way through them. Unfortunately they only seem to provide temporary solutions, then the problem recurs. I spent over an hour on the telephone with my isp, IONOS and deleted the domain then restored it from a backup. For a time it worked fine. Then the problem with being timed out ( I am using Microsoft Edge, most of the time) started happening again. When ever i click to Update the site it throws me out with the timed out error. Sometimes when i wait for 2-5 minutes the site reappears, but not always. Sometimes i try closing it and opening a new tab to reopen it. That does not always work either.

I nearly forgot, I have deactivated all of the plugins. I can control this from my server. I am absolutely baffled as to what is causing this series of timed out errors. I have also rebooted both my laptop and the router a few times. I would be very grateful for any help in resolving this,

Many thanks

David

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