How does Unicom card open sp short message service?

Sp short message service, that is, Unicom's letter service, can be used without opening it yourself. However, if you block or connect the letter function, you cannot use it. You can directly call local 100 10 for consultation to restore Unicom's convincing function. If you are a user of Guangdong Unicom, you can send "hfyw" to 10655 133 and "KTYW" to 106559342, and you can apply for restoring the convincing function of Unicom. China Unicom tips ".