Slavia APP 661 co2 pistol shooting full auto

When I bought this pistol it was leaking bad. I replaced a seal and it holds and fires .The problem is when I insert the 7 shot clip it emptys out all 7 rounds.Full auto. It supposed to be semi auto. It's a pretty cool piece in really good condition. And I would love to get it shooting like it should. If anyone has any knowledge and or has worked on this pistol their input would be much appreciated. 

Thanks and stay safe, Ron 
 
I don't own that pistol you mention however I have noticed co2 and some PCP semiauto pistols as well as rifles go into full auto mode when the gun senses it's low on co2 or air like the end of its useful co2 cart or low on charge or the sear not catching or resetting properly as it should. Have you emptied the co2 then load the magazine first before inserting a fresh co2? YO!