Custom Extraction Model | Train a new Model | Build Mode "Template" not available

Hi Team,

I am trying to detect if a document has 2 signatures on PDF. I am using a "Custom Extraction Model" and using "Draw Region" to draw the signature region and label it. However, when I click on Train model, I am not able to select "Build Mode" as "Template". (Image attached). The reason I need this enabled is as per documentation https://learn.microsoft.com/en-us/azure/ai-services/document-intelligence/concept-custom?view=doc-intel-3.1.0#custom-document-model-types, the signature detection will only work with Build mode Template and not neural.

Could anyone help here please?

Note: I have verified that both document in training model are of exact same structure.

Thanks!