Facing issue to create signer placeholder in the uploaded document

Dear,

I have a dotnet application to upload document and e-sign by Adobe e-signing API v6. I am trying to add a placeholder for the signer in the document. here is the screenshot of the document below. It is a PDF. I want to replace signer1 signature and initials with the fields.

My upload is successful by the API call "/transientDocuments". And then I am calling API "/agreements" with the transientDocumentId. In my request I am sending the state as "AUTHORING" and not mentioning any email address. because I do not want to sent it for the signature. I want to see the document with the placeholder fields in Adobe. here is my JSON input for agreement API call.

{
"name": "Test update Object",
"type": "AGREEMENT",
"signatureType": "ESIGN",
"state": "AUTHORING",
"message": "",
"participantSetsInfo": [
{
"memberInfos": [
{
"securityOption": {
"authenticationMethod": "NONE"
},
"placeholderName": "SIGNER1"
}
],
"role": "SIGNER",
"order": 1,
"participantSetId": "signer1"
}
],
"fileInfos": [
{
"label": "Test update Object",
"transientDocumentId": "CBSCTBABDUAAABACAABAAdMEEYQ1ihLB-T744N2DGmtU5alSbpeWh_UrmOtS1BPbzNkHm2b9jXTUET7m31wkeLUanyG65Qj9AqlLed6_1jy6HnCSMBQgw489ue1nlgrQDpmy3KkgDb_gS_Psm*****3eK8UU6oqzFivSBYBBLc41k-__NQlKI3LJ3X2dN0qdIkAzTTq-aVHxTd8d0Kn-5gYX3VukUtj_yV8mBqu459EaGDLsKTJVeSV2VV6S-i74GGg-yf5ydH0ukWhLwUGtkhwbe8vDvkhmVVVVV-Fq7UCm21JhMufpvsEswn6c1yHtF2XV_tzqtqhQ_Ls3_V1yP1VZdLKlLQV3lXG2kVH6P45PT9kODkNJ0xNsjpy8Q*"
}
]
}
  

Here is my error in the log: 

Metadata
x-request-id : 6fd35876-f836-4b75-a016-a0dc96fdf3c9
content-type : application/json
status : 400

Body
{
     "code": "CONTENT FILTERED",
     "message": "Either email or phone delivery info field is expected but none found."
}

What I am doing wrong? Could you please help me out?

Should I explicitly enable something for my adobe account for the dynamic placeholder ?

Many thanks in advance.