Why can't mobile phones send text messages in groups?

Take Android phones as an example. How to deal with the problem that Android phones can't send short messages in groups;

First, make sure the selected contact phone number is a normal phone number, and check whether it contains special characters, e-mail, etc.

Second, it is recommended not to send too many contacts at once.

3. Settings-Applications-Information-Clear data and cache, and remind you to back up important messages.

Fourth, download information group software tried to send text messages in groups.

5. Change the machine and card, contact the place where the card problem belongs, and restore the backup data of the mobile phone problem to the factory or contact the after-sales treatment.