Problem with operating two FMU blocks in one simulink simulation

Hello,

i have a problem with the co-simulation of two fmu blocks. Each of the fmu-block only contains a matlab-system function and some in- and outputs.

When i simulate the converted simulink model (fmu-block 1 and 2) of each function separatly, everything works fine. Also the whole system is working when i connect both mathlabs-system-functions in one simulink model. But when i connect the two fmu blocks in an other model (as seen below in the sketch), simulink throws an error.

This is the error message i recieved:

"Error in supplied FMU: An error occurred in function 'fmi2Instantiate' for block 'Sim_FMU5' during simulation. To debug your FMU file, select the "Enable FMU Debug Logging" check box. For more information, see the FMU troubleshooting documentation."

The solver is in each model the same, also the step time. The Debug Logging didn´t help to find the mistake.

Can somebody help me?

Tank you for your support :)

Kind regards

Tobias