[MM3-users] Held Message view, JSONDecodeError: Invalid control character

I am running the Debian 10 mailman3 and mailman3-web packages with mariadb. I received an email to the list from an invoicing software and now I am unable to view or accept this email from the list. All other lists seem to be still working fine. I'm guessing there is a piece of data in my database that is corrupt or unable to be decoded, but I am at a loss on how to find and fix it. Any help would be greatly appreciated

Sep 11 12:29:23 2020 (11577) 127.0.0.1 - - "GET /3.1/lists/redacted@redacted.com/held?count=0&page=1 HTTP/1.1" 200 90
Sep 11 12:29:23 2020 (11577) REST request handler error:
Traceback (most recent call last):
  File "/usr/lib/python3.7/wsgiref/handlers.py", line 137, in run
    self.result = application(self.environ, self.start_response)
  File "/usr/lib/python3/dist-packages/mailman/database/transaction.py", line 50, in wrapper
    rtn = function(*args, **kws)
  File "/usr/lib/python3/dist-packages/mailman/rest/wsgiapp.py", line 216, in __call__
    return super().__call__(environ, start_response)
  File "falcon/api.py", line 215, in falcon.api.API.__call__
  File "falcon/api.py", line 189, in falcon.api.API.__call__
  File "/usr/lib/python3/dist-packages/mailman/rest/post_moderation.py", line 160, in on_get
    resource = self._make_collection(request)
  File "/usr/lib/python3/dist-packages/mailman/rest/helpers.py", line 159, in _make_collection
    for resource in collection]
  File "/usr/lib/python3/dist-packages/mailman/rest/helpers.py", line 159, in <listcomp>
    for resource in collection]
  File "/usr/lib/python3/dist-packages/mailman/rest/post_moderation.py", line 150, in _resource_as_dict
    resource = self._make_resource(request.id)
  File "/usr/lib/python3/dist-packages/mailman/rest/post_moderation.py", line 70, in _make_resource
    resource = super()._make_resource(request_id)
  File "/usr/lib/python3/dist-packages/mailman/rest/post_moderation.py", line 39, in _make_resource
    results = requests.get_request(request_id)
  File "/usr/lib/python3/dist-packages/mailman/database/transaction.py", line 85, in wrapper
    return function(args[0], config.db.store, *args[1:], **kws)
  File "/usr/lib/python3/dist-packages/mailman/model/requests.py", line 120, in get_request
    result.data_hash, expunge=False)
  File "/usr/lib/python3/dist-packages/mailman/database/transaction.py", line 85, in wrapper
    return function(args[0], config.db.store, *args[1:], **kws)
  File "/usr/lib/python3/dist-packages/mailman/model/pending.py", line 142, in confirm
    value = json.loads(keyvalue.value)
  File "/usr/lib/python3.7/json/__init__.py", line 348, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python3.7/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.7/json/decoder.py", line 353, in raw_decode
    obj, end = self.scan_once(s, idx)
json.decoder.JSONDecodeError: Invalid control character at: line 1 column 21 (char 20)