Why can't Apple's 6s SMS im be activated?

The specific operation of Apple's 6s SMS ims activation is as follows:

Go to Settings -I cloud- Find my iPhone and select Close. It is better to delete the "Delete Account" below. Multiple accounts may make it impossible to set up according to the account you applied for.

Re-apply for a free apple ID on the computer. Be sure to remember the password and enter the first step to change the account number to the new application ID.

Note: If the ID and password you applied for have not been changed, they will be set according to the old password when activated.