This is a way to express love with digital homophony. The origin of this digital password comes from the network language, which is a very popular use of numbers to represent Chinese characters on the network.
158 was also given some good wishes, such as "I want to stay with you all my life, make a fortune all the way, have a smooth love, a smooth career, a prosperous business, a rolling wealth, a happy life, good luck and everything goes well."