DEBMAS inbound IDOC is not creating the text

I have an inbound DEBMAS interface with internal number range set for the customer master. I am populating the text and an idoc is successfully created.But the text fields are not coming in on the newly created customer master.

Is it possible that the customer must be already present and  E1KNA1H-TDNAME must already be populated with an existing customer for the texts to be created ? Should I break the step into 2 process 1) Create generate customer master and get the newly created customer master number 2) Populate the text for the newly created customer master ? Any tip is welcome.