Volume up/down button not working problem

@egealpkavas first make sure that this is not a software issue. Check in settings and see if there is a software update available for your phone. If so, perform the update. Next place your Mediapad into safe mode Here you can check if it is another App that may be causing this. If your Volume button still has the same issues in Safe mode, it is most likely a hardware issue.

Your Mediapad uses a volume button & power button flex cable that may be damaged. Consider replacing it. There are no specific guides for this. I recommend that you use something like this videoand once you are in your Mediapad. Locate th flex and see how it is installed. Then try to replace it. You are looking for a flex like this (Example only, not an endorsement.)

While you work on your tablet, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has the same problem as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.