The model number of the installed FPGA is different.

PolarFire Video KIT (MPF300-VIDEO-KIT)
Older PolarFire Video KITs are equipped with the MPF300TS, which has a security suffix of S.​
This product is discontinued.

PolarFire Video KIT Non-S (MPF300-VIDEO-KIT-NS)
NS = abbreviation for non-security.
The new kit features the MPF300T without the S suffix.

Please refer to the following website for details.
https://www.microsemi.com/existing-parts/parts/150747

If necessary, change the model number of the Demo project for PolarFire Video KIT to the model number of your development kit.