The Consumer Rights Act applies to transactions made by an individual consumer or consumers, and a business. Since a b2b contract is made between two businesses, the Consumer Rights Act does not apply.
Consumers and businesses have different rights and protections offered by the law.
For example, a term that excludes liability from a business to consumers is invalid. However, businesses need to specifically check in advance if there are clauses excluding certain liabilities when buying as a business.
A consumer is not acting as a business when making a purchase. Therefore a business is not a consumer and not protected by the Consumer Rights Act.