What are you sewing? According to a couple of sites, it is because of the weight or size is pulling it. But, I'm thinking that perhaps the feed dogs and/or the foot need adjusting. I'm wondering if one of these sites would help?
https://seamwhisperer.com/fabric-pulling-left/ https://sewingmachinetalk.com/sewing-machine-pull-left/
Janey - Neat people never make the exciting discoveries I do.
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