Error code 1138 of doing voltage sweep on 2450 by Kickstart

When I try to do the linear sweep on 2450 by Kickstart, once I clicked the 'run' button. It will pop up '' Error: My 2450: 1138 Parameter, 2, expected type 'tmodel_block', but found type 'nil' '' on the event log. And the instrument could not do the sweep. 
The connection is good, and the Kickstart could recognize the instrument. All the setting of the sweep panel are able to modify. The Kickstart version is 2.9.0, and the firmware version is 1.6.7c.
I've tried to look up the errror code on the manual but found nothing. I was so confused by this. Could anyone can help me with this. Thanks in advance!

Hello,
I would recommend updating to the latest firmware version found at the link below and see if that fixes this bug, as we may have patched it in a previous release.

Model 2450 Firmware Revision 1.7.12 and Release Notes | Tektronix

Let us know if this works!