Problem contacting the server

Platform, device version and operating system:
PC (Steam)

Screenshot or image:

What you were expecting to happen, and what actually happened:
I read various bug reports about server issues, however, this one seems different, so I decided to create a new one. I get the message shown in the screenshot above on various occasions. I had it, when I was trying to start a battle, I had it after a succesful battle, also when I was trying to enter guild task screen and maybe on other occasions. When the bug happens, the loading bar or the loading gems cycle for about a minute, after that, the message appears. So far, it was always sufficient to NOT follow the suggestion in the message. So I do NOT restart the game, I just click on “Retry” and the game proceeds immediatelly with whatever I was trying to do (start battle, show victory screen, enter guild tasks screen…). From what I can see up to now, the bug doesn´t do any harm, I do not lose resources, sigils, trophies, whatever. It´s just annoying, as it increases the loading time by the said minute…

How often does this happen? When did it begin happening?
Happened several times to me since some days. I can´t remember exactly since when, I am sure it was already present last weekend. So it is for sure not caused by the weekly reset.

Steps to make it happen again
From what I saw up to now, this bug appears totally random. Up to now, I have no idea, what causes it and so also no idea how to make it happen.