Hi there,
I'm afraid I'm not familiar enough with HTTParty to give you an answer on that, but essentially, what you want to have at the HTTP level is metric=AD_REQUESTS&metric=EARNINGS&metric=CLICKS
In other HTTP clients, that's achieved by assigning an array to a key, as you mention, and the client handles the rest.
Could you take a look at the logs to see what your request string looks like?
Cheers,
Sérgio
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Sérgio Gomes
Developer Relations
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