Parking Lot Troubles

Hi,

Using FreePBX 2.11.0.38 with Parking Lot 2.11.0.15. Secretary is complaining that sometimes when she puts a call into the Parking Lot it just disappears. We’ve had one caller say they heard the message of “Parking Lot is full”, which, in our scenario, should never happen (10 parking spaces but only 6 lines).

They are using an Aastra 9143i using a BLF key programmed as follows:
type: blfxfer
value: 70

Anyone have any ideas?

Thanks,
Westley