Nipype error: No design image generated by FEAT Model

I’m having an issue running my first level analysis in Nipype. For some reason, when running FEATModel, I’m getting an error that says it can’t generate a design image.

Everything until that point appears to be working fine. Has anyone else encountered this before? I’ve gone very deep into the source code and can’t figure out the cause. A snippet of my code is below.

level1design = Node(Level1Design(bases = {'dgamma':{'derivs': False}},
                            contrasts = contrast_list),

analysis1st.connect([(modelspec, level1design, [('session_info',

level1estimate = MapNode(FEATModel(output_type = 'NIFTI_GZ'), 
                     name = "level1estimate", iterfield=['fsf_file', 'ev_files'])

analysis1st.connect([(level1design, level1estimate, [('ev_files',

As an update, here are my traceback errors from Nipype:

211123-15:51:50,278 nipype.workflow INFO:
[Node] Executing “_level1estimate0” <nipype.interfaces.fsl.model.FEATModel>
211123-15:51:50,593 nipype.interface INFO:
stderr 2021-11-23T15:51:50.592781:terminate called after throwing an instance of ‘std::logic_error’
211123-15:51:50,595 nipype.interface INFO:
stderr 2021-11-23T15:51:50.592781: what(): basic_string::_S_construct null not valid
211123-15:51:50,676 nipype.interface INFO:
stderr 2021-11-23T15:51:50.676046:Aborted (core dumped)

It seems my issues begin with this std::logic_error, but I really don’t know any C++ so am at a loss how to solve this!