What does it mean to wish you a happy old age?

Wish you a happy old age is a greeting in the late Spring Festival.

In traditional Chinese culture, people pay New Year greetings to each other and express their best wishes during the Spring Festival. Generally speaking, the first to fifth day of the Lunar New Year is the main time to pay New Year greetings, which is called "Worship the New Year in the early years." After the fifth day of the Lunar New Year, when people meet, they will say "Wish you a good old age", which is a later way of greeting the New Year. This custom reflects the tradition of people expressing care and blessing to each other in the New Year.