Google Cloud Shell disabled for account

I'm using GCP for some time now and few months ago when I tried to open Cloud Shell from browser I received this message:

I'm preety sure that it is a mistake. I wonder if anyone faced that problem before. The browser shell is not that important but it's nice to have. Is there any way I can restore access to this? I don't care about the files in home directory, just access to the shell.

What I've tried:

• Sending appeal as the message suggests, which opens pop-up that says Send feedback (I didn't receive any response)
• I found this support contact https://cloud.google.com/contact but it says Contact sales (does not really fit for the case)
• I also checked this question Google Cloud Shell has been disabled, where answer says To solve this issue you should follow instructions received in the message from Google. However I didn't get any e-mail from Google about that.

Unless you have a connection at Google who can help or a Googler reads this, without paying for Cloud Support you're falling (presumably intentionally) between the cracks.

The feedback is likely tracked but, as you suspect, it's likely low priority. BTW, you can check your reports to Google Feedback. This should confirm that this one at least made it into the system.