Please contact your host provider and tell them your issue. Ask them to check is there anything from their side.
This is very uncommon issue. We haven't faced any such type of issue, There are many pages on your site is not working.
Also don't forget to check all third party plugins by deactivating them.
Steps:
- deactivate all third party plugins.
- Save permalinks once.
- check all links are working perfectly or not.
if all links are working perfectly that means it was an issue of third party plugin.
so by installing one by one check which one is faulty.
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