Unable to detect the presence of page cache

I am running Ubuntu Server 22.04 LEMP server with Nginx, wordpress, php8.1, & MariaDB, and Modsecurity.

With Modsecurity enabled, on my wordpress health screen I am getting the following errors that should be improved:

Unable to detect the presence of page cache

Unable to detect page cache due to possible loopback request problem. Please verify that the loopback request test is passing. Error: cURL error 56: OpenSSL SSL_read: error:0A000126:SSL routines::unexpected eof while reading, errno 0 (Code: http_request_failed)

Page cache enhances the speed and performance of your site by saving and serving static pages instead of calling for a page every time a user visits.

Page cache is detected by looking for an active page cache plugin as well as making three requests to the homepage and looking for one or more of the following HTTP client caching response headers:cache-control, expires, age, last-modified, etag, x-cache-enabled, x-cache-disabled, x-srcache-store-status, x-srcache-fetch-status.

With Modsecurity disabled, I get no such errors.

Can someone please help me figure out how to fix this?

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