Businesses generally can't charge people for goods or services they didn't request or approve. Consumers who receive goods or services they didn't request aren't required to pay for them. The consumer also won't be liable for losing or damaging the goods (unless this was caused by their wilful and unlawful conduct).
A business won't be in breach of the law if it can prove that it had reasonable grounds for believing that it was entitled to the payment, or the invoice made it clear that the person receiving it wasn't required to pay any money. While these exceptions may allow businesses to avoid penalties, the customer still doesn't have to pay for any goods or services they didn't request, but the business is allowed to take the goods back.
For more information, visit the Pricing and surcharging and Unfair business practices pages.