TypeError: Cannot create property 'headers' on string 'Cannot merge user p2rhuvnye into itself!'

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View details in Rollbar: https://rollbar.com/freezy/server/items/51/

TypeError: Cannot create property 'headers' on string 'Cannot merge user p2rhuvnye into itself!'
  File "/var/www/server/production/v3.2.3/node_modules/@koa/cors/index.js", line 94, in cors
            err.headers = Object.assign({}, errHeadersSet, headersSet, { vary: varyWithOrigin });
  File "<anonymous>", line unknown, in <unknown>
  File "internal/process/next_tick.js", line 189, in process._tickCallback