Amazon MWS error

Traceback (most recent call last):
File “/home/frappe/frappe-bench/apps/frappe/frappe/utils/background_jobs.py”, line 100, in execute_job
method(**kwargs)
File “/home/frappe/frappe-bench/apps/erpnext/erpnext/erpnext_integrations/doctype/amazon_mws_settings/amazon_methods.py”, line 20, in get_products_details
report_id = request_and_fetch_report_id(“GET_FLAT_FILE_OPEN_LISTINGS_DATA”, None, None, market_place_list)
File “/home/frappe/frappe-bench/apps/erpnext/erpnext/erpnext_integrations/doctype/amazon_mws_settings/amazon_methods.py”, line 89, in request_and_fetch_report_id
report_request_id = report_response.parsed[“ReportRequestInfo”][“ReportRequestId”][“value”]
TypeError: byte indices must be integers or slices, not str