When you modify TCPIP profile and want to apply new parameter. You can use following command:
VARY TCPIP,tcpip-procname,OBEYFILE,tcpip profile dataset(member)
Note : Some of reserved ports are not released, then you need to restart TCPIP.
Reference:
https://www.ibm.com/docs/en/zos/2.5.0?topic=SSLTBW_2.5.0/com.ibm.zos.v2r5.halu101/varyp1b.html