Webhook not will not fire (assume not defined correctly, and recipients question)

Greetings Everyone,

I have successfully created the following subscription on an enabled target. The target URL is confirmed working with the headers provided (tested independently):

{
"Data": {
"Item": {
"SubscriptionId": "~",
"Entity": "AbEntry",
"Op": "Update",
"TargetId": "f745a .. b918a",
"Recipients": [ "no-reply.com" ],
"Filter": [
{ "Type": { "$EQ": "Individual" } },
{ "Udf/$TYPEID(57998)": { "$EQ": "7" } }
]
}
}
}

Assume the above states: Upon update of any AbEntry object that is type "Individual" AND the UDF with typeid = 57998 (i.e., Rating) with a value of 7 (our display value is: OPEN), fire the URL within the target?

We are not seeing any activity. Please advise. Additionally, assume that the "Recipients" object is for reference only and no emails are actually sent?

Thanks, Joe