@ZiadMuhammedX

Remove all the cables from monitor.   Press and hold the power button of monitor for 1 min.    Connect all the cables back.  Try to turn on the monitor.   Connect the monitor to computer and check. If the cable is non removable please don't try to remove it. 

Try to use alternative cables and check if possible.

On the monitor – use the control buttons.   There will be an option to reset monitor settings to default.    Try to reset the monitor and check.  

To isolate the issue, try to use the same monitor to a different computer and check  or  Try to use an alternative monitor on this computer and check.

@ZiadMuhammedX

I am really sorry for the inconvenience.

If your monitor is in warranty you can contact the warranty dept.     Go to the website support.acer.com - chose your country.   On the new page - scroll down -  click on "contact support".  Scroll down.  You can find the phone no to contact the warranty dept. 

If it is out of warranty, please contact local store or

Go to the website support.acer.com - chose your country.   On the new page - scroll down -  Click on  "Repair My Acer" - Request to have your Acer product repaired.   There will be charges for repair. 

Additional info to contact Acer Store:  Please visit the website - support.acer.com - chose your country - click on shop.   You can buy desktop, laptop, monitor and accessories.  Alternatively,  on the top right corner you can find the phone no to contact Acer store.   For the parts which are not available on Acer store, you have to contact local store.