CDB3-4659 500 error while posting list instead of object

[2023-05-23T07:53:36.190Z] | prozorro_sale.jobber.errors | ERROR - Unknown error caught in API - 'list' object has no attribute 'get' | X-Request-ID: 72087F000001AC847F0000010050646C71009A882F35
Traceback (most recent call last):
  File "/jobber/prozorro_sale/jobber/errors.py", line 127, in request_errors_middleware
    return await handler(request)
  File "/usr/local/lib/python3.9/site-packages/prozorro_sale/auth/__init__.py", line 269, in context_middleware
    return await handler(request)
  File "/usr/local/lib/python3.9/site-packages/prozorro_sale/auth/__init__.py", line 286, in access_middleware
    return await check_access(handler)(request)
  File "/usr/local/lib/python3.9/site-packages/prozorro_sale/auth/__init__.py", line 312, in handler
    return await func(request, *args, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/prozorro_sale/tools/__init__.py", line 90, in retry_on_concurrency_error_middleware
    return await handler(request)
  File "/usr/local/lib/python3.9/site-packages/prozorro_sale/tools/__init__.py", line 72, in handler
    return await func(request, *args, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/prozorro_sale/tools/middlewares.py", line 49, in request_unpack_params
    return await handler(request, *args, **request.match_info, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/prozorro_sale/tools/errors.py", line 67, in handler
    return await func(request, *args, **kwargs)
  File "/jobber/prozorro_sale/jobber/api/handlers/redemption.py", line 112, in upload_cancellation
    return await _common.upload_cancellation(REDEMPTION_TYPE_MAPPING[redemption_type], request, obj_id)
  File "/jobber/prozorro_sale/jobber/api/handlers/_common.py", line 145, in upload_cancellation
    cancellation = _obj.Cancellation(data, role='owner')
  File "/jobber/prozorro_sale/jobber/models/core/base.py", line 17, in __init__
    super().__init__(data, **kwargs)
  File "/usr/local/lib/python3.9/site-packages/schematics/models.py", line 101, in __init__
    f_value = data.get(field, Undefined)
AttributeError: 'list' object has no attribute 'get'