When use 'Call Web Service' node, Appian appears to be sending optional

When use 'Call Web Service' node, Appian appears to be sending optional XML tags with empty values.

For example, assume that this is a complete XML according to the schema.

<contact>
          <name>ABC</name>
          <email>abc@abc.com</email>
</contact>

<email> is an optional element according to the schema. If email is not mapped to a variable, Appian is sending:

<contact>
          <name>ABC</name>
          <email></email>
</contact>

This is not desired. How do I get Appian to send:

<contact>
          <name>ABC</name>
</contact>

(I am new to Appian)

Thanks in advance.
...

OriginalPostID-129608

OriginalPostID-129608