Page cache. Slow server response time

Hello everybody.

We use the free version of WP Fastest Cache.

We recently encountered the following error using the WP “Site Health” plugin.`

“The page cache has been detected, but the server response time is still slow
Page cache improves the performance of your site by saving pages and serving them statically rather than calling them from scratch on each user visit.
The page cache is detected by looking for a cache plugin in addition to executing three homepage requests and looking for the following HTTP response cache headers:
cache-control, expires, age, last-modified, etag, x-cache-enabled, x-cache-disabled, x-srcache-store-status, x-srcache-fetch-status.
The average response from the server is 1,864 milliseconds. It should be less than the recommended 600 milliseconds.
There was 1 response in the client cache: last modified.”

The site is in a windows environment. What should we do?

Thank you
The staff

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