All MH flights booked directly with them is only a 5-digit PNR. When you book through a travel agent, you usually get a 6-digit PNR but sometimes 5. The PNR booked through a travel agent will definitely be different to the one generated by MH. What I've done in the past is ring MH directly and they've matched my travel agent's booking PNR with the PNR on their own system and they advised me to use the MH-generated one when making enquiries about that booking when I'm calling them. However, MH have a policy (as do other airlines) that when you've booked through a travel agent, any changes/requests have to go through that travel agent and not with MH directly.