A tally entry key must be enabled at the agent station.
The tally key is an F1039 if it is setup correctly in the PBX.
Go to CM9000>Station,key#>F1039
E.g for a tally key on key 8 of station 3200.
9000>3200,08>F1039
The list of available tally codes are in the Call Center Worx Features and Specifications Manual.