Why I received Internal server error??

Problem:
I received Internal server error when I request to create task in folder by API v4.
Of course the Authorization bearer is included.

I received this message↓
{"errorDescription":"Internal server error","error":"server_error"}

Please tell me how to resolve this.

Action:
curl -g -X POST -H 'Authorization: bearer xxxxxxxxxxxxxxxx' -d 'metadata=[{"key":"testMetaKey","value":"testMetaValue"}]&description=Test task description&dates={"start":"2019-03-05","due":"2019-03-12"}&title=Test task&parents=["xxxxxxxxxx"]&status=Active' 'https://www.wrike.com/api/v4/folders/xxxxxxxxx/tasks'