Sending an ACME HTTP validation request to kasdivi.com results in an unacceptable redirect. This is most likely a misconfiguration of your web server or your web application.
It appears that a redirect was generated by your web server that is missing a trailing slash after your domain name: https://kasdivi.com.well-known/acme-challenge/letsdebug-test. Check your web server configuration and .htaccess for Redirect/RedirectMatch/RewriteRule.
Trace:
@0ms: Making a request to http://kasdivi.com/.well-known/acme-challenge/letsdebug-test (using initial IP 209.160.65.133)
@0ms: Dialing 209.160.65.133
@224ms: Server response: HTTP 301 Moved Permanently
@224ms: Received redirect to https://kasdivi.com.well-known/acme-challenge/letsdebug-test
A test authorization for kasdivi.com to the Let's Encrypt staging service has revealed issues that may prevent any certificate for this domain being issued.
209.160.65.133: Fetching https://kasdivi.com.well-known/acme-challenge/ixyKvqSj6dX61e-zPTs_RYR4KsAuv0SzBKwmrSLlS1Q: Invalid host in redirect target "kasdivi.com.well-known". Check webserver config for missing '/' in redirect target.