Generally speaking, the validity period of a credit card is 3 years, and it is ok to activate it during the validity period. However, some banks stipulate that the card will be automatically cancelled if it is not activated within six months after the card is issued, and the landlord can call the customer service staff of the bank specially. If there is no such provision, it can be used before the expiration date. This is what I learned. If the landlord wants to know other information, he can check in official website, where I love my card. It's quite reliable I hope my answer can be made.