Pages with custom domain returns 404 Not Found

Description of the problem

The Page with custom domain (http://skylee.co) suddenly return 404 Not Found which displayed normal previously. But https://skyleeco.gitlab.io is able to display.

DNS settings on Namecheap.com:

A Record @ 52.167.214.135
CNAME Record * skyleeco.gitlab.io.
TXT _gitlab-pages-verification-code.skylee.co gitlab-pages-verification-code=79502caea59c822596cd4b6e147b5470
TXT _gitlab-pages-verification-code.www.skylee.co gitlab-pages-verification-code=47f8bf63cb9b99d2bca2d7f535a96ed2
URL Redirect Record www htt://skylee.co Permanent 301

Which Group/Project (with full path) is experiencing the issue?

https://gitlab.com/skyleeco/skyleeco.gitlab.io

Approximate date/time when the error occurred.

Not sure when it started.

Describe what you were doing right before the issue occurred.

Changed DNS settings but it seems not working.