Hey there I have a 6J 2015 seat Ibiza TSI, had a new change currently fitted had issues ever since. Worked out EPC And engine light comes on and it misfires and loses power, it drives fine few a month then it happens again. Worked out number 2 spark plug keeps popping out on it own?! And I’ve had it pushed back in twice nice and it’s been fine no doubt in a month it’ll happen again?! Has anyone experienced this? Or has managed to fix it?! The garage(dodgy and took advantage of me) put in cheap £10 spark plugs at first then I said put in Bosch. Still having this issue, would anyone recommend a new expensive set? Or is there another way to keep the spark plug in? 
many thanks!!!