Hello Sam,
welcome to this moderated Azure community forum.
This error is a strange one.
I was able to replicate the error message in the Azure portal.
The workaround seems to be to limit the property name length to 64 characters like:
AIOC-NAE13ProgrammingAHU-2-Zone-Dat-ResetAmerescoDATAmeresco_DAT
Then the body is accepted.
I have contacted someone I know from the team.
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