Error on chian code

When I start the demo, I get an error on chaincode:

[b4bd4084]Received message QUERY_ERROR from shim
07:10:25.247 [chaincode] HandleMessage -> DEBU 28e [b4bd4084]Handling ChaincodeMessage of type: QUERY_ERROR in state ready
07:10:25.247 [chaincode] HandleMessage -> DEBU 28f [b4bd4084-f87f-4cca-abaf-b6d9b5547110]HandleMessage- QUERY_ERROR (QUERY: Error retrieving caller details: Couldn't get attribute 'role'. Error: Failed retrieving extension.). Notify

Could you please give me some advise?

[liam-grace]

How are you starting the demo and what platform are you using?