Pasta machine rolls dough wider than machine
You might be rolling the dough too thinly, too soon. Start by feeding a somewhat flattened 'disk' of dough through the pasta machine at its widest setting. Change the setting by at most 1 for each subsequent pass.
You might also benefit from 'laminating' the dough: after the first pass, fold the dough in thirds, turn it 90 degrees and pass it through the machine again. Here is a picture demonstrating the procedure from the Serious Eats &quot;Science of the Best Fresh Pasta&quot; guide.