s 45 Calling line identity not to be concealed
45. Subject to section 48(3), a person that makes a voice call containing a specified message or causes a voice call containing a specified message to be made or authorises the making of a voice call containing a specified message, addressed to a Singapore telephone number, from a telephone number or fax number, must not do any of the following:(a) conceal or withhold from the recipient the calling line identity of the sender; (b) perform any operation or issue any instruction in connection with the sending of the specified message for the purpose of, or that has the effect of, concealing or withholding from the recipient the calling line identity of the sender.[40/2020]