I have verizon, but Im sure the companies have similar policies.
If you have an account I would go to sprint.com and sign in and look at a recent or current bill and look at what you are currently being charged for. Then somewhere you should be able to look at calls and texts in more detail and it should give you all the phone numbers and times you sent the texts.
If you have an account I would go to sprint.com and sign in and look at a recent or current bill and look at what you are currently being charged for. Then somewhere you should be able to look at calls and texts in more detail and it should give you all the phone numbers and times you sent the texts.