The 9558 text message said that I opened a mobile banking, but I didn't do anything. What is this ...

It is possible that someone accidentally filled in the wrong mobile phone number and opened it. I suggest you check whether the last number of that short message is yours.

Another is that you may have checked the option when opening Taobao or the bank will be opened automatically. It is best to go to the bank business hall for detailed inquiry. If you don't need to cancel.