Adobe Sign API Create Web Form issue : use exist template

How to use the template in Adobe sign API POST /widgets API.

I can't get transientDocumentId of Template.

Please help me with this.

I have found the solution.

$.ajax({
...

data: JSON.stringify({
    fileInfos: {
      libraryDocumentId: "{libraryDocumentId}" // instead transientDocumentId
    },
    ...
  })
})