Smart cases activate sleep mode also from the back

Hello,

i have changed the touch screen of the iPad Air Wifi.

Right now i have the problem with the smart cover. When i open it and but on the back of the iPad it will put it on sleep mode. Some one can help me to figure out what could be the problem. The home button flex is the original one. I have tried to disassemble the magnets on the right side. NO WAY TO FIX THIS PROBLEM.

I hope someone can help me.

Best regards