What should I do if I can't receive SMS after Samsung mobile phone root?

Hello, this can be restored with App Store. If it's because root didn't receive the text message after that, remove root.

You download a PC version of the application treasure directly from the computer, then connect the mobile phone, open the software and wait for the mobile phone matching software. Then you open "My Phone" at the top of the software and enter the toolbox in the left frame. After input, there are six tools on the right. The sixth one is "one-click root" and then click in to remove root from your mobile phone. Refer to the figure below for details.

That's it. You should be able to receive messages normally.

I am very willing to help you solve your confusion, if this answer helps you. I also hope to adopt more, thank you!