Income not collected properly

Platform, device version and operating system: Windows 10 64-bit version 2004

Screenshot or image: Not available

What you were expecting to happen, and what actually happened:
I went to the game to collect my income. When clicking on the gold on my home kingdom, I saw the income delivery popup, but it showed no income at all. Zero gold. I clicked out of the popup and clicked my home kingdom again. I received the same result. I don’t know how many times I did this but I didn’t receive any income or tributes to my knowledge.

How often does this happen? When did it begin happening?
This only happened once. People have been reporting that the game has been very slow today.

Steps to make it happen again
I do not know how to replicate this isssue. It happened only once.