NC Remote Control with Damaged Buttons: How to Open and Clean Contacts Safely (Model: ydhakk8n)

Hello,
Some of the buttons on the remote control do not work. I want to clear contacts, because the pilot has his years already.
I am asking for a hint:
How to undress the remote control so as not to break the housing latches?
Unscrewing the only visible screw after removing the battery did not help.
Model as per photo:
http://tinyurl.com/ydhakk8n

A problem similar to: https://www.elektroda.pl/rtvforum/topic2652118.html, but this does not fully solve my case.
greetings

Gently and gently again. A small flat tool for this. It can be a screwdriver, but it must be very flat and quite wide.

Hello - it can be helpful;
https://dogotowania.pl/noze-na-sztuki/2486-nozyk-solingen-mały-6cm.html
And an old ATM card or a dice on the guitar.

mihal2002 wrote:

krzad wrote:

Some of the buttons on the remote control do not work.

It goes to APS NC + to replace faulty equipment.

Thanks for the creative advice, although the answer is not a question.
The advice would be OK if the pilot was under warranty and not - as in my case - he was several years old. I know I can buy a new remote. For now, I would like to try to resuscitate a copy that I used so far.

Besides, I see that my imprecise question it triggered advice that was not exactly what I wanted.
I can not imagine opening the remote with a tool other than flat and sharp. BTW - I'm rather good at theory.

Therefore, I will clarify the question:
From which end / which side to begin to undermine the case of the remote control, so as not to break the internal latches?

I would like to ask for answers from people who have practically practiced the opening of this or a similar pilot model.
greetings