Ram is sold in kits for a reason.
A motherboard must manage all the ram using the same specs of voltage, cas and speed.
The internal workings are designed for the capacity of the kit.
Ram from the same vendor and part number can be made up of differing manufacturing components over time.
Some motherboards, can be very sensitive to this.
This is more difficult when more sticks are involved.
Ram must be matched for proper operation.
Ryzen is more sensitive to ram issues than intel.
You could give it a shot on an intel pc.
Match the specs as to speed, voltage and timings.
At the very worst, you would have 16gb and the same single channel performance you have now.
If both sticks play nice, you will have 24gb of which 16gb will be...