Mobile phone short message reception shows that you can't receive information when the storage is full, so switch to the memory card. Why can't the memory card receive information when the space is no

Mobile phone short message reception shows that you can't receive information when the storage is full, so switch to the memory card. Why can't the memory card receive information when the space is not full? Both mobile phones and sim cards have an upper limit for receiving short messages. Generally, SIM card can only store 50 messages, while mobile phone can store 50- 1000 messages. If they are full, they can't receive messages. If they want to receive information, they must delete or transmit short messages. What needs to be clearly distinguished is that the memory card can not store short messages, but can store data, similar to a USB flash drive. Only mobile SIM card, Unicom UIM card and Netcom Ping An card can store short messages.