Thank you very much for your reply. I checked the log and found that the HTTP integration is not set-up for reverse proxies. And I found the following thread which solved the problem: HTTP integration is not set-up for reverse proxies? - #4 by mahikeulbody
I added - 127.0.0.1 and - ::1 to read:
http:
use_x_forwarded_for: true
trusted_proxies:
- 172.30.33.0/24
- 127.0.0.1
- ::1
and now it works. Thank you.