What the pills actually are
Pills are small knots of fibre formed as the surface rubs in use. Clothing, throws and frequent seating can increase friction. Some pilling can occur even on a good fabric, so the question is how much, how soon and where.
Take photographs before treating it. A close-up alone hides whether the problem is local or widespread.
Clean and treat with care
Check the manufacturer's fabric code and care instructions. Avoid vigorous scrubbing or pulling fibres loose. A suitable fabric shaver may help some materials, but it should only be used according to the supplier's advice.
If a new sofa develops heavy pilling rapidly, contact the seller before attempting a home remedy. You may need an assessment under the product terms.
Choose a better fabric for the next job
Bring a photo of the pilling and explain who uses the sofa, whether pets are involved and how it is cleaned. Handle actual upholstery samples and ask about abrasion, care and the supplier's aftercare policy.