Symbol Not Found: 'getTextDimensions'

Hoping someone can help me out.  I'm trying to run a simple watch face on Forerunner 55.

Everything runs fine in the simulator, but crashes on the device.  What am I missing?

---
Error: Symbol Not Found Error
Details: "Could not find symbol 'getTextDimensions'"
Time: 2022-08-06T22:29:23Z
Part-Number: 006-B4033-00
Firmware-Version: '5.07'
Language-Code: eng
ConnectIQ-Version: 4.1.5
Filename: Forerunnerface
Appname: Forerunner face
Stack: 
  - pc: 0x300043e8
  - pc: 0x1000065b
    File: 'C:\Users\willj\vscode\Forerunner\Forerunnerface\source\ForerunnerfaceView.mc'
    Line: 198
    Function: <globals/ForerunnerfaceView/<>updateWatchOverlay>
  - pc: 0x100003d2
    File: 'C:\Users\willj\vscode\Forerunner\Forerunnerface\source\ForerunnerfaceView.mc'
    Line: 133
    Function: onUpdate

I'm using SDK version 4.1.5; The app is configured for min. SDK version 3.2.0, watch is running IQ 3.3.1

This is the referenced code:

private function updateWatchOverlay() as Void {
        var clockLayerDc = _clockLayer.getDc();

...

var clockHourMinuteText = new WatchUi.Text({
                :text=>timeString,
                :color=>Graphics.COLOR_LT_GRAY,
                :backgroundColor=>Graphics.COLOR_TRANSPARENT,
                :font=>Graphics.FONT_NUMBER_MILD,
                :justification=>Graphics.TEXT_JUSTIFY_CENTER,
                :locX =>WatchUi.LAYOUT_HALIGN_CENTER,
                :locY=>WatchUi.LAYOUT_VALIGN_CENTER
            });
clockHourMinuteText.draw(clockLayerDc);  //line 198