With Cloudflare proxy enabled, a blank page is displayed

I have enabled the Cloudflare proxy for my PHP website. It worked for awhile and then after a few days, it started showing a blank page. If I turn the proxy off, so its just doing DNS, then the page loads correctly, so my site is working properly. I turn the proxy back on and it works fine for a few days and then starts showing the blank page again. So something is strange when Cloudflare is in front of my site.

While it was broken, I ran curl -v and got this output.

$ curl -v https://movienight.tips

*   Trying 2606:4700:3031::ac43:b1c1:443...
* Connected to movienight.tips (2606:4700:3031::ac43:b1c1) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*  CAfile: /etc/ssl/cert.pem
*  CApath: none
* (304) (OUT), TLS handshake, Client hello (1):
* (304) (IN), TLS handshake, Server hello (2):
* (304) (IN), TLS handshake, Unknown (8):
* (304) (IN), TLS handshake, Certificate (11):
* (304) (IN), TLS handshake, CERT verify (15):
* (304) (IN), TLS handshake, Finished (20):
* (304) (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / AEAD-AES256-GCM-SHA384
* ALPN, server accepted to use h2
* Server certificate:
*  subject: CN=*.movienight.tips
*  start date: Oct 30 18:15:16 2022 GMT
*  expire date: Jan 28 18:15:15 2023 GMT
*  subjectAltName: host "movienight.tips" matched cert's "movienight.tips"
*  issuer: C=US; O=Let's Encrypt; CN=E1
*  SSL certificate verify ok.
* Using HTTP2, server supports multiplexing
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* Using Stream ID: 1 (easy handle 0x7fa70f012c00)
> GET / HTTP/2
> Host: movienight.tips
> user-agent: curl/7.79.1
> accept: */*
> 
* Connection state changed (MAX_CONCURRENT_STREAMS == 256)!
< HTTP/2 200 
< date: Tue, 15 Nov 2022 02:46:14 GMT
< content-type: text/html; charset=UTF-8
< set-cookie: ss=eyJzaSI6IjE1MWI3MjU1MWEyZWI2N2FiYTEzNjM3MmZkNzZiNDdhNCIsInVpIjoiM2ZkMTM3ZTQ1ZDJlYmI3NmY5Mjc2MzcyZmQ3NmI0N2E4IiwiYW4iOjB9; expires=Tue, 22-Nov-2022 01:26:14 GMT; Max-Age=600000; path=/; domain=.movienight.tips; HttpOnly
< vary: Accept-Encoding
< cf-cache-status: DYNAMIC
< server-timing: cf-q-config;dur=5.9999874792993e-06
< report-to: {"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v3?s=0rm0nc5mBMUzq3bA1oc%2FUpjHGDmpK3q8xerT4hAxRCY9N4AmMRjwuVmGg1KjJcGju29O8Df7jC8msxlaGsPpGcIRaV%2FVKJGtmyY%2Fy%2BbvN4CUeZJ1NPo11NOIpTmmx1If2%2BVfJvnIN%2FX3FKIqR8s%3D"}],"group":"cf-nel","max_age":604800}
< nel: {"success_fraction":0,"report_to":"cf-nel","max_age":604800}
< server: cloudflare
< cf-ray: 76a4a7c4bcc90d3c-LAX
< alt-svc: h3=":443"; ma=86400, h3-29=":443"; ma=86400
< 
* Connection #0 to host movienight.tips left intact

Does anyone know what is going wrong based on this output? Cloudflare is only sending the headers and sends no body in the response. I have all the default settings in Cloudflare for this website.