I got a turbo tax authorization code texted to my cell phone today. Why?

That is a Validation Number being sent to your cell phone.

If you don't want it to be sent to your cell phone here are the steps to assist you with that:

1. Log in TurboTax Account
2. Top screen, click My Account> Account Settings
3. Click on Security>input your cell number
4. A verification code will be sent to your phone

•  Once your cell phone number is verified, the next time you have the code sent, you will be given a choice to send the validation code to your cell phone instead of email.
  

need validation code? many numbers called to me but none of them worked

@4414 Are you trying to get into your account and can't?  

Account recovery

How can I check the activity in my TurboTax account?

Resetting the devices that can access your TurboTax account