Help Adding Contact to Quote Rest API

Hello,

I try to add contacts to Quote but only get the error below

Non-success response detected from server: Non-success response detected making REST request: BadRequest. Full content is {“HttpStatus”:400,“ReasonPhrase”:“REST API Exception”,“ErrorMessage”:“Object reference not set to an instance of an object.”,“ErrorType”:“Ice.Common.BusinessObjectException”,“ErrorDetails”:[{“Message”:“Object reference not set to an instance of an object.”,“Type”:“Error”,“Table”:“QuoteCnt”,“Program”:“Epicor.RESTApi.Common.dll”,“Method”:“ThrowUpdateExtException”,“ColumnNumber”:17,“LineNumber”:27}],“CorrelationId”:“f29a85b2-89aa-4580-bf74-8d7d636a28c4”}

used path “/Erp.BO.QuoteSvc/QuoteCnts”

Body

{
“Company”: “XCOMP”,
“QuoteNum”: 6436,
“ConNum”: 95,
“PerConName”: “Alec”,
“Name”: “Alec”,
“Func”: “”,
“PhoneNum”: “5622-2493”,
“Fax”: “”,
“EmailAddress”: “alec@x.com”,
“PrimeContact”: false,
“PerConID”: 15454,
“RowMod” : “A”
}