AWS Cognito – SerializationException (Start of structure or map found where not expected)


I have created a user in Cognito user pool, using the create user option as shown in the image, and want that user to set a new password on first Log In. For this I am using below given method, as given in the AWS documents
Create User from AWS


Below is my code

After executing this I get an error saying,

{code: “SerializationException”, name: “SerializationException”,
message: “Start of structure or map found where not expected.”}

These are the attributes which I have selected in User Pool

List Of Attributes and permissions in user pool

Please help me to solve this.


In my case it ended up being malformed data being sent to my resetPassword helper. The function was looking for three parameters (username, code, password):

… and I was sending them as an object:

I just updated the helper and I was all set!

Just log your data in the setNewPasswordForAdmin function and I’ll bet you’ll find something awry there.

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