Make sure you have bind plug plugged into the receiver as well and power it up first then like @Dugdog47 said on the transmitter/radio side of things. Should see light go from flashing to solid or otherwise change pattern once radio binds to the receiver you may have to hold the bind button while it "finds"/binds to the receiver.
Yah binding is always a lot of fiddle with protocol and or order of doing things or most recently have used CLI for tiny hawk binding process I think in general the RX is supposed to be powered first and the TX "finds" the RX and stores connection to it since the RX could have multiple TXs that could send it signals; I haven't tried this with two trying to send at the same time to one bound thing but now I'm kinda curious does it just stick with the first thing that starts transmitting to it or does it get wildly confused because now two things that are bound to it are sending it info. With bluetooth pairing (at least in the older spec) only allowed two devices to communicate but TX/RX pairing is slightly different in that you can have different transmitters that all send control signals to the same quad.
I don't think the one TX to multiple RX is normally possible with common radios but the ones with 4 in 1 radio that includes nrf chipset at least physically could do this and broadcast to multiple receivers but not super practical in most cases for flying since wind etc. is slightly different for each quad if trying to control multiple... side track but something @Dugdog47 and I have discussed a little before as well.
@wafflejock if the receiver send rssi I don't see how that world work because the tx would be receiving multiple signals and would probably get confused lol. However I'm willing to bet using receivers that don't send rssi such as the FS-A8S could bind with one tx and multiple receivers.
I've been so busy lately shopping for houses and getting ready to move and haven't had time to build but hopefully in a few months I'll be back to posting my experiments.
@T121DKY I've encountered aio tiny whoop boards with built in fs receivers that say they'll bind with afhds2a protocol but it turns out only afhds will work and it was very particular in the order that you had to bind tx, bind kwad, and even turning your tx off and unplugging your kwad in the right order seemed to matter.
Ok deep breaths
It's Friday,tomorrow is the last day of the week
Looks like Saturday night is date night with a whoop so.
There is room for different interpretations of the instructions based on broken English
On a different note I don't seem to be able(smart enough) to upload pics keeps saying file too big
Oh yeah that would be handy
Hold bind button on quad
Power it keeping it held till blue led flashes
Set remote to bind
Blue light goes solid but the remote stays saying binding
Power down remote then quad
But importantly when u power up the quad and remote again put the left stick to the bottom right to arm
Most FCs will accept bf or cf, your choice. Usually I'll select betaflight but if it's an older board longer supported by bf, cleanflight 2.5 works just as well as betaflight 3.7. It's the betaflight 4.xx that is questionable although the times I've used it it worked exceptionally well.