Error while editing SEO

I have a proeblem with editing or imporving of SEO.

I use Yoast SEO. I edit SEO of web site. But when I save settings, web site does not save it. It says : 500 Internal Server Error : Request Timeout. This request takes too long to process, it is timed out by the server. If it should not be timed out, please contact administrator of this web site to increase ‘Connection Timeout’.

If you need I can share login informations of my web site .