There are 2 adjustments you need. you need to contact the 510 of your atty and you need to allow for different battery lengths. Most mechanical mods have 2 adjustments and you just need to find them on your mod.
First place I would try is the store where you got the mod.
Next is try here.
Finally try to find it yourself. some mods have the 510 pin as a screw inside another screw so you need to adjust them to your atty and battery. Some have a spring for the 510 and something else that screws to adjust for the battery. Spend some time looking at the mod and I am sure you will find it.