Duplicate a Learning Remote Key Fob

I have a project that I am working on that uses a couple of Amazon circuit modules to turn a remote outlet on for a set time period. I have the Wireless Remote Switch ,12 V 1 Channel Rf Relay Transmitter and Receiver momentary switch with Battery (1CH) connected to a count down-timer relay board and the circuit is working like I need but I want to add more remote fobs.
I have two of these transmitter/receiver sets and can "teach" my receiver to recognize either of my remote fobs but not both at the same time. I have not had any success with a Google solution for cloning my remote fobs.I have also tried holding the fob buttons for extended periods of time but have not seen any change in the LED status to indicate that I might have changed into some type of learning mode. There are no internal DIP switches on the fob circuit board either.The remote fob is ZL-JX302.
How do I clone this remote fob?
Thanks in advance for the help.
SM