A friend here in Spain who bought his 12FG in USA also suffered the same trouble and the shop offered changing it as it proved impossible to correct and we all understod it was just a malfuntion. No other 12FG at my club has showed that fault even no one at the spanish distributor for which I help with the spanish manual translations and we checked a few ones!.

So it is best you contact the shop and try getting a different one.

Best Regards

Jesus Cardin