Zoho Flow Webhook - Wrong syntax 'size' when executing webhook

Zoho Flow Webhook - Wrong syntax 'size' when executing webhook

I have a webhook from GitHub set up. The webhook inside of Zoho Flow can receive a payload from GitHub, but when I click "Test", I get an Input and Output button. Input is blank, and Output says "Wrong syntax 'size'". I am not sure if I have something configured incorrectly or if there is a bug. Please advise. Thank you.