How spoofing works?

Did you ever get SMS from binance where it states you are withdrawing funds and they provide you with OTP number? They also state in this SMS to call a certain number if you are not withdrawing your funds. And you are most definitely not withdrawing anything. The worst thing is this SMS is shown as if it came from same binance number from which you already got legit messages before. How can it mask like that? Binance support say this is spoofing and SMS should be deleted and no links or numbers should be called.