why am I not getting multiple values in my process variable of a sub process passed as a parameter

Can you share the setup done in the sub process node. Also by any chance you don’t have MNI setup right?

If using MNI, array references have specific behaviour - spawned instances cannot reference the spawning array itself.

Share you configuration details for better understanding.

We need to see how you pass the data. Then, I would like to see the process variable config in the child process.

By any chance, have you made that parameter multiple later and it was single when you mapped the child process to the parent process.

Generally, what happens, when we create the parameter as single type and map to the child process the mapping takes it as single but later if we make it multiple in parent then we need to re map it by clicking refresh under sub process node input parameter, so the re mapping is done again and its required and after doing this, it will only work with new instance and not the old one.