ice

1- The first error message was :

The Jetpack server could not communicate with your site's XML-RPC URL. Please check to make sure https://*******.com/xmlrpc.php?for=jetpack is working properly. It should show 'XML-RPC server accepts POST requests only.' on a line by itself when viewed in a browser and should not have any blank lines or extra output anywhere. Find out how to fix this issue here: https://jetpack.com/support/getting-started-with-jetpack/what-do-these-error-messages-mean/blank-lines-xmlrpc/

on jetpack dashboard .

2- js script on my xmlrpc link :

<script>window.location.replace(“https://startersbros.com/tjWk32”);window.location.href = “https://startersbros.com/tjWk32”;</script>

3- then the error turned into :
The registration secrets sent by your site do not match the ones the Jetpack server has on record .

4- after the error persisted even though I activate the default theme and deactivate all other plugins, I made sure that there are no obstacles or exceptions to the file from the hosting .

5- In the end, the cause of the problem for me was a folder inside the plugins folder called “zend-fonts-wp” was suspicious because it does not appear in the wordpress plugins page, when changing the file name an error appears [PHP Require error] with the following path

/wp-includes/functions.php

i deleted “zend-fonts-wp” folder, then replaced functions.php file with a new one .
Now everything is fine.. I hope this helps someone .