Hello,
Hope you are doing well.
What SDK version are you using? Could you let me know what modifications you implemented in the code, in both client and server sides? Were you able to implement the code with 2 custom services (prior to adding the third service)?
Were you able to follow the KW38 Custom Profile guide? On the "Client (Collector)" section of the guide, the modifications needed in the BleApp_StoreServiceHandles are mentioned. The gBleSig_CService_d macro should be defined in the eatt_central.h and eatt_peripheral.h files of your projects, as well as all the corresponding variables and macros for that service.
For more information about this, you can also refer to section 7 of the "Bluetooth Low Energy Application Developer Guide" which describes the services and the declarations needed.
If you would like to reference an example that implements multiple services, I would recommend checking the Private Profile Server/Client examples from the QN9080 SDK, the application implements a custom GATT based Private Profile for Battery Service, Device Info Service and Private Profile service and can send data from client to server.
Best Regards,
Ana Sofia.