I'm having some issues using python library bioblend with galaxy. Creating a new history, adding files and invoking a workflow works. But the workflow never actually starts. The jobs have all been in the queue for weeks. Maybe I'm forgetting a step? Could someone here help me?

This is my code:

import sys
import os
from bioblend import galaxy
import re

GALAXY_URL = '...'
API_KEY= '...'

file_list = [
# list of filenames to search in shared data libraries
]

def main():
    gi = galaxy.GalaxyInstance(url=GALAXY_URL, key=API_KEY)
    sysbio_library = gi.libraries.get_libraries(name =  'NAME')
    files = gi.libraries.show_library(sysbio_library[0]['id'], contents=True)
    workflows = gi.workflows.get_workflows(name = 'WORKFLOWNAME')
    # unlist by keeping only element in list
    workflow = workflows[0]
    # show details of workflow
    #wf = gi.workflows.show_workflow(workflow['id'])
    # see inputs needed
    # wf['inputs'] # ==> '0' : forward read ; '1' : reverse read

    # get list of files in folder sysbio_library (is also list)
    files = gi.libraries.show_library(sysbio_library[0]['id'], contents=True)
    for i in file_list:
        forward_file = list(filter(lambda file: re.search( (i+"1"),file["name"]), files))
        reverse_file = list(filter(lambda file: re.search( (i+"2"),file["name"]), files))
        if forward_file and reverse_file:
            # should have only 1 match, we need first element of list 
            forward_file = forward_file[0]
            reverse_file = reverse_file [0]
            new_history_name=forward_file['name']
            hist = gi.histories.create_history(name=new_history_name)
            dataset_F = gi.histories.upload_dataset_from_library(hist['id'], forward_file['id'])
            dataset_R = gi.histories.upload_dataset_from_library(hist['id'], reverse_file['id'])
            # create empty dictionary
            datamap = {} # or datamap = dict()
            # specify inputs, source = history data 
            datamap['0'] = { 'src':'hda', 'id': forward_file['id'] }
            datamap['1'] = { 'src':'hda', 'id': reverse_file['id'] }
            w = gi.workflows.invoke_workflow(workflow['id'], inputs = datamap, history_id=hist['id'])
            print('Created new history for ' + i)
        else:
            print(i +' not found.')

if __name__ == '__main__':
    main()