I used the instructions on this page to bind 2 HC05 modules: https://howtomechatronics.com/tutorials/arduino/how-to-configure-pair-two-hc-05-bluetooth-module-master-slave-commands/
This worked very well for me.
Are you able to enter AT mode to make the changes? If not, this tutorial may help: Setting HC05 (ZS-040) to AT mode