Why do you always remind me that there is not enough storage space when there are few SMS messages?

I think you have too much software. You can move some software to the memory card, so there will be more memory in the phone. It is also possible that the memory of the mobile phone is not large enough to store many things, so don't store too many useless things. If the memory of the mobile phone is quite large and files may be hidden, it is necessary to delete some unused files on the computer so as to save more useful things.