Bitmap native color format venusq2

Working on a watchface for amoled watches ...

Code works fine in sim for all amoled models except Venu Sq 2 (even Venu Sq 2 Music works fine), which gives an exception

on a line using drawBitmap2 saying "Source must be native color format". My bitmap is a png (tried fiddling with packingFormat).

Could this be a sim issue (I wouldn't think Venu Sq 2 and Venu Sq 2 Music have graphics differences)?

What is the meaning of the exception, any way to avoid it?

Using sdk 6.4.2 ...