Problem connecting two independent simulink models leading to incorrect output

Hi there!

I have two matlab models: a DC-DC converter and inverter. Each of the models runs independently well using the same sample time. However, the DC-DC converter takes 25 s while the inverter takes 125s to run for one second. I tried to use function-call subsystems as proposed in Problem when two Simulink models are combined. - MATLAB Answers - MATLAB Central (mathworks.com) but got the following error:

Goto/From connections cannot cross nonvirtual subsystem boundaries. The only exception is when a goto is connected to a state output port

Component:Simulink | Category:Model error

Invalid connection starts with 'FINAL_SIMULINK2/powergui/EquivalentModel1/Yout/Goto88'

Component:Simulink | Category:Model error

Invalid connection ends with 'FINAL_SIMULINK2/Function-Call Subsystem/Current Measurement1/source'

How can I solve this problem? Is there any other way of connecting the models to obtain an accurate output?