The pay regs for all three services (or rather, the single pay regs as they are becoming once we all line up under JPA) state that you are responsible for the accuracy of your pay, and that any problems should be reported via Unit Administration Staff, if you have any left. Failing that, JPA Help Line once more. It's quite incredible that you can be debited the personal contribution for HTDs without HTDs being in issue. Simple coding laziness, failing to write a rule which checks this.....