hi im using playsms with kannel on ubuntu php7.
my question is how can i hide sender number with some text. what steps should i follow ?
not sure, but i guess you need to change "sender id" in playsms config, and your provider must support this.
You can only hide change the sender number if you have an SMPP account as far as I know when using a modem it will assume the modem number irespect of your settings.