Coinbase Pro API Invalid Signature ColdFusion - coldfusion

Question

I'm trying to get simple account info from Coinbase Pro and can't seem to figure out the CB-ACCESS-SIGN header. I keep getting an "invalid signature" message.
From Coinbase Pro API Docs:
The CB-ACCESS-SIGN header is generated by creating a sha256 HMAC using
the base64-decoded secret key on the prehash string timestamp + method
requestPath + body (where + represents string concatenation) and base64-encode the output. The timestamp value is the same as the
CB-ACCESS-TIMESTAMP header.
The body is the request body string or omitted if there is no request
body (typically for GET requests).
The method should be UPPER CASE.
My Code:
<cfscript>
accessKey = 'xxx';
passPhrase = 'yyy';
theSecret = 'zzz';
// create an epoch time stamp
theTime = now();
utcTime = dateConvert('local2UTC',theTime);
ISOtimeStamp = dateFormat(utcTime,"yyyy-mm-dd")&"T"&timeFormat(utcTime,"HH:mm:ss")&".761Z";
timeStamp = numberFormat(dateDiff("s","January 1 1970 00:00",ISOtimeStamp) + 28800.761,"_.000");
requestPath = '/accounts';
theBody = "";
method = "GET";
// create the prehash string by concatenating required parts
what = '#timeStamp#' & '#method#' & '#requestPath#' & '#theBody#';
// decode the base64 secret
theKey = binaryDecode(theSecret,"base64");
// create s sha256 hmac with the key
theHmac = hmac("#what#","#theKey#", "HMACSHA256");
// encode the result
cas = toBase64(theHmac);
</cfscript>
<cfhttp url="https://api.pro.coinbase.com/v2/accounts" method="get" result="y">
<cfhttpparam type="header" name="CB-ACCESS-KEY" value="#accessKey#" >
<cfhttpparam type="header" name="CB-ACCESS-SIGN" value="#ucase(cas)#" >
<cfhttpparam type="header" name="CB-ACCESS-TIMESTAMP" value="#timeStamp#" >
<cfhttpparam type="header" name="CB-ACCESS-PASSPHRASE" value="#passPhrase#" >
</cfhttp>