Why does my favicon appear on the Amazon S3 endpoint, but not in the forwarded domain?

I tried my best and don’t understand why my icon still doesn’t appear. If I told you how much time I spent trying to figure this out, you will understand why I am on the verge of losing my mind.

Here is a summary [I am not technical, just starting to learn, so please bear with me]:

I use Amazon S3 as my host. GoDaddy is DNS, and I have a forwarding with mask settings so that the Amazon endpoint is directed to the actual domain.

Here's the strange thing - the icon appears on the endpoint of the Amazon, but not in the forwarded domain where I want it to appear. The icon also appears when I test using Dreamweaver.

I can assure you that this is not a matter of clearing the cache, as I have done this many times and conducted tests to make sure that it works. I tried all possible variations of the code variations and nothing works. I am convinced that this is not a problem with the code, cache, file, but rather something else that is beyond my knowledge.

So, I came to Stackoverflow.

Please, any help will be HIGHLY appreciated!