PC app WD My Cloud - "Login not authorized"

I have one question for you. I have had WD My Cloud 3 TB for several years and I have been able to connect to it from an external network until recently. However, now the program for Windows 10 reports “Login not authorized” when I log in by email + password after selecting the desired device. I uninstalled the program, including removing data from the registry, file system, etc., unfortunately, the same problem occurred after the new installation. I haven’t changed my cloud settings lately - I have remote access enabled. Android app works on external network via email and password in order.
Do you know how I can solve the problem?
Thank you very much in advance for every answer,

@kajicek94 What type of network is it, private, public, business, Educational etc? Are you trying to login by using files.mycloud.com ?

I have logged in on your link and could see/edit my files. My home network is private and the external network is also private. I don’t block any specific ports, etc. Thanks for reply