[Решено] The translated pages do not appear or are ocmpletely broken

Background of the issue:
I placed all translations inside but when I switch the wpadmin language to the translated language (Englsih), the pages were not appearing. I was using manual translation and the advanced editor. I was trying then with duplicating content but it didn't work out. Then followed the instructions to do a reset of WPML, but it didn't help.

Symptoms:
The translated pages do not appear or are completely broken.

Questions:
Why are the translated pages not appearing when I switch the wpadmin language to English?
Why didn't duplicating content work for the translations?
Why didn't resetting WPML resolve the issue?