Answer: by giving reasonable notice that strict performance will be required
Explanation:
This law strictly has to do with contract modifications and sale of goods. It should be noted that an agreement that modifies a contract in this particular article does not need any consideration for it to be binding.
Once a party has waived rights to a portion of a contract that has not yet been performed, that party may retract the waiver when a reasonable notification has been gotten by the other party that is involved that there will be a strict performance that will be required of the term that has been waived, unless in situations whereby the retraction can be seen as being unfair due to the material change that occur.