Why do telecom mobile phones always send short messages to some mobile phones slowly, while others are received the next day?

1, the mobile phone and the card may not match well, and the compatibility is not good. There is something wrong with the mobile phone itself. You can try another card. 3. The problem of cell phone signal is hard to say. It may be that the cell phone signal usage rate in your area was relatively high at that time, or there was a transmission problem in your base station. For more service benefits, click on "official website" customer service 324 below to answer your questions.