File not found error: amcatnlo_configuration.txt

Dear experts,
I am trying to generate a gridpack for the pp > w + Njets process, and the generation stops after ~1 hour of running on the NLO step with the following error:
...
INFO: Generating born Feynman diagrams for Process: s s~ > w+ s u~ QCD<=2 QED<=1 [ all = QCD ] $$ t t~ h @2
copying generated process to working directory
INFO: Using default PDF sets for run3 production
starting NLO mode
No module named 'madgraph'
 No hepmc reader since No module named 'madgraph' [lhe_parser.py at line 50]
INFO: ************************************************************
* *
* W E L C O M E to M A D G R A P H 5 *
* a M C @ N L O *
* *
* * * *
* * * * * *
* * * * * 5 * * * * *
* * * * * *
* * * *
* *
* VERSION 5.2.9.13 20xx-xx-xx *
* *
* The MadGraph5_aMC@NLO Development Team - Find us at *
* http://amcatnlo.cern.ch *
* *
* Type 'help' for in-line help. *
* *
************************************************************
Traceback (most recent call last):
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/./bin/generate_events", line 111, in <module>
    launch = run.aMCatNLOCmd(me_dir=root_path)
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/bin/internal/amcatnlo_run_interface.py", line 1418, in __init__
    CmdExtended.__init__(self, me_dir, options, *completekey, **stdin)
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/bin/internal/amcatnlo_run_interface.py", line 296, in __init__
    super(CmdExtended, self).__init__(me_dir, options, *arg, **opt)
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/bin/internal/common_run_interface.py", line 674, in __init__
    self.set_configuration()
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/bin/internal/amcatnlo_run_interface.py", line 1643, in set_configuration
    return super(aMCatNLOCmd,self).set_configuration(amcatnlo=amcatnlo, **opt)
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/bin/internal/common_run_interface.py", line 3607, in set_configuration
    self.set_configuration(config_path=me5_config, final=False, initdir=self.me_dir)
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/bin/internal/amcatnlo_run_interface.py", line 1643, in set_configuration
    return super(aMCatNLOCmd,self).set_configuration(amcatnlo=amcatnlo, **opt)
  File "/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/bin/internal/common_run_interface.py", line 3617, in set_configuration
    config_file = open(config_path)
FileNotFoundError: [Errno 2] No such file or directory: '/afs/cern.ch/work/y/ymaravin/MC/UL/3pi/genproductions/bin/MadGraph5_aMCatNLO/WTo3Pi_5f_NLO_FXFX/WTo3Pi_5f_NLO_FXFX_gridpack/work/processtmp/Cards/amcatnlo_configuration.txt'
finished pilot run
cleaning unneeded files from gridpack

Any help on how to resolve this would be really appreciated, thanks!
Yurii