Once one was authorized, others came and copied it. The logic is that the virus is allegedly naturally occurring, so a test for it can't be patented. Of course the first one, which was completely made up and not based on any observation, accounted for 70% of the PCR for covid done in 2020 - and as such immensly profitable - it was made by Christian Drosten, who had been trying to preempt a "viral epidemic" and get the first test on the market for about a decade before hand.