Missing Pages after SSL certificate installation

Hi,

Our hosting provider recently installed an SSL security certificate on our SFTP. Since then all home pages except the home page have stopped working and have a 404 error. I have tried updating th permalinks an dupdated all other links from http to https and still they are not working.

I can see the pages in the back end of WordPress but when trying to edit/update or publish them it either says ‘updating failed’ or ‘publishing failed. I can’t even add new pages or I get the same error when going to publish.

Can anyone help?

I have tried everything I can find on the internet so far on the issue or similar.

Thanks

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