Date entry issue - ERROR_CODE_INPUT_ERROR ... "Invalid timestamp format"

I'm trying to input a date in Bravo Vision, to my database, which is in Xano. Everything is properly tagged and bound, however, when I send the input through, I receive a 400 error. In Xano, the output indicates the following:

code: ERROR_CODE_INPUT_ERROR,

message: Invalid timestamp format.,

payload: {param},

traceId: 6e72d97a-0679-479c-8542-1f80466531db

My understanding is that both Xano and Bravo are passing this info in ISO 8601 format? I'm not understanding the reason it's returning an Invalid timestamp format.

To clarify, these are DATE inputs (both tagged in Bravo, and how the entry is structured in my database), not timestamps.