Help with XML api device configuration

[MarvinThomas]

I'm looking for a solution to automate sdwan deployments so I'm trying to do a couple of things with this api call:

1 - create the layer3 subinterface interface

2 - give the subinterface an ip and next hop ip

3 - enable sdwan on the interface and give it an sd wan profile

Here is the url:

api_url = f"https://192.168.1.1/api/?type=config&action=set&xpath=/config/devices/entry[@name='localhost.localdo...}"

element = """
<entry name="ethernet1/1.1851">
<ipv6>
<neighbor-discovery>
<router-advertisement>
<enable>no</enable>
</router-advertisement>
</neighbor-discovery>
</ipv6>
<sdwan-link-settings>
<upstream-nat>
<enable>no</enable>
</upstream-nat>
<enable>yes</enable>
<sdwan-interface-profile>sdwan_dia_1</sdwan-interface-profile>
</sdwan-link-settings>
<ndp-proxy>
<enabled>no</enabled>
</ndp-proxy>
<adjust-tcp-mss>
<enable>no</enable>
</adjust-tcp-mss>
<ip>
<entry name="209.56.139.18/29">
<sdwan-gateway>209.56.139.17</sdwan-gateway>
</entry>
</ip>
<interface-management-profile>internet</interface-management-profile>
<tag>1851</tag>
<comment>Windstream DIA</comment>
</entry>
"""

This is the response i see:

{'response': {'@status': 'error', '@code': '13', 'msg': {'line': 'set failed, may need to override template object first'}}}

Any suggestions are welcomed.  Thanks.