Problem controling low temp on vision pro kamado

So I smoked my first rack of spare ribs yesterday on my new vision kamado pro. I loaded the firebox with royal oak lump and lit it with a weber parafin cube. I let it burn for about 10 minutes then added the volcanic stone for a diffuser and closed the top vent to a 1 and the bottom vent to a 1. I slowly brought the temp up to 275 (took about an hour)and closed the top and bottom vents to barely open. I put on the ribs and the temp held steady between 270-275 for 2 hours. At the 2 hour point I rotated the ribs because I wanted to see if I had any hot spots. Everything looked good at this point. I came back and hour later and the temp was 350. I opened the kamado and the ribs were done. The ribs turned out a little overdone but the were actually very good. My question is can opening the lid for maybe 30 seconds cause the temp to rise like that? Also after i took the ribs off I closed all the vents down at this point the temp was 350, three hours later and the temp was only down to 250. Is this normal for a kamado grill?

I tested my dome thermometer in boiling water and it was Accurate and I was using a maveric on the grate so that's not the problem. I'll try using the soaked wood chips and looking for air leaks.

Top vent is completely closed looks like it is leaky. Any suggestions on how to fix this. Thanks.