Problems with M2 Shell carrier

[Bravo470]

Can anyone offer any assistance with this slightly annoying problem.I have a brand new Benelli M2 I have had it around six months and put just over 1000 cartridges through it.Very occasionaly after inserting the first cartridge you are unable to push the shell carrier down therefore you are not able to insert the second cartridge.The carrier is jammed tight and will not push down.When this has occured I have ejected the first cartrige and reloaded and every thing appears to be ok.This week I shot at the local clay ground and out of 100 targets it did this around four times.Has anyone any anwsers and how can I correct this Regards Jon

[Matt D]

Make sure the bolt is completely closed and the bolt head is rotated or the shell carrier will not go up.