Temporal Event causing Illegal Access (Out of Bounds)?

This issue seems to only be happening to a user who had a refurbished 935, the app crashes immediately. I'm not sure what is causing the Illegal access, If anyone can lend a hand it would be very much appreciated.

Crash log caught from running a test version

---
Error: Illegal Access (Out of Bounds)
Details: 'Failed invoking <symbol>'
Time: 2021-01-29T17:03:29Z
Part-Number: 006-B2691-00
Firmware-Version: '21.00'
Language-Code: eng
ConnectIQ-Version: 3.2.1
Filename: CORREC~1
Appname: 'App Name'
Stack: 
  - pc: 0x30004c91
  - pc: 0x301057ad
  - pc: 0x10000623
    File: '/Users/Yada/Yada/Yada/Background.mc'
    Line: 49
    Function: onTemporalEvent

Here is where I register for the temporal event.

class appName extends app.appbase {
    init() {
    
        regForTempEvent();
    
    }

	function regTempEvent(){
		if (Toybox.System has :ServiceDelegate) {
			canDoBG = true;
			Background.registerForTemporalEvent(new Time.Duration(5*60));
		}
	}
}

Here is the background service delegate

(:background)
class BgServiceDelegate extends System.ServiceDelegate {
	
	function initialize() {
		System.ServiceDelegate.initialize();
	}
	
	// callback function
	function onReceive(responseCode, data) {
		
		if (data == null) {
			data = {};
		}
		data["responseCode"] = responseCode;
		Background.exit(data);
	}
	
	function makeRequest() {
		if (Communications has :makeWebRequest) { 
			var userName = App.getApp().getProperty("userName");

			if (username == null) {
				username = "";
			}
			
			var url = Lang.format($1$", [username]);

			var options = {
				:method => Communications.HTTP_REQUEST_METHOD_GET,
				:responseType => Communications.HTTP_RESPONSE_CONTENT_TYPE_JSON
			};

			Communications.makeWebRequest(
				url,
				{},
				options,
				method(:onReceive)
			);
	
		}
	}

	function onTemporalEvent() { 	
		makeRequest();
	}
}