WARNING: COMPUTATIONS FAILED TO CONVERGE. The routing time step is too large, try reducing it. - Visual OTTHYMO

I am working on a VO model I get the following warning for one of the RouteChannels at the end of the model:
WARNING: COMPUTATIONS FAILED TO CONVERGE.: The routing time step is too large, try reducing it.
The time step is 1 min, I tried to reduce the time step but apparently, the min value is one min. Any idea how I can get rid of this warning?

Answer:
The routechannels have some limitations. To remove the limitation, our team has designed compoundchannels. Please replace the routechannel that has the problem with a compoundchannel.
ROUTECHANNEL and COMPOUNDCHANNEL

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