Dumb question from a rookie baker: No stiff peaks when whipping egg whites

Yes, it is easier to separate eggs when they are cold. Room temp whites beat up fluffier. I always wipe the glass bowl with white or cider vinegar before whipping the whites.
I don't know if Swerve substitutes well for regular sugar in this case. Sometimes, the substitute ingredients behave funny in baking (alternative butters,egg whites from a carton etc)

Yes, it is easier to separate eggs when they are cold. Room temp whites beat up fluffier. I always wipe the glass bowl with white or cider vinegar before whipping the whites.
I don't know if Swerve substitutes well for regular sugar in this case. Sometimes the substitute ingr

It's easier to separate the yolks and whites when they are still cold from the refrigerator, then bring the whites to room temperature. This helps ensure there is no yolk in the mixture to inhibit the formation of stiff peaks.

The first thing that comes to mind is fat. When you were separating your eggs, did even a speck of yolk get in with the whites? Or, did you use a plastic bowl? Plastic bowls have microscopic slits in them from everyday use and fat can hide in them. They’re hard to clean completely. Either of these scenarios will inhibit egg whites from inflating to their optimum volume.

Also, and I don’t know the answer to this, but are you completely sure you can use Swerve successfully in beating egg whites?