Frigidare Gallery Washer belt walks into drum

I’ve noticed a rubbing sound in the washer recently when it’s spinning. I looked in the top while it’s running, and it seems to be the drive belt tracking toward the drum and rubbing against it when it spins. I’ve even noticed some wear marks and small grooves in the drum. I replaced the pulley, screw, and belt, and it’s still happening. I’ve noticed a small amount of travel front and back in the drum, and I wonder if that shouldn’t be there… suggestions would be appreciated!