Some planes don't want to TR with just aileron but I don't think the Magic is one of them. The ailerons on mine seem to get it going. I can still only do a few rolls at a time

but I'm working on it.
Try:
Calm day. Wind can make it harder to TR.
Pump the throttle, even bounce the plane up and down once or twice. The throttle bursts sometimes get the roll started.