Programming one new key 2016 CX-5 GT (lost key)

I lost one of our two keys to our 2016.5 CX-5 GT or maaaybe my child flushed it down the toilet. Is it possible to self program one additional key to match the existing one we have? Or do BOTH keys need to be wiped and re-programmed?

I purchased a replacement OEM key fob with lock/unlock/hold which matches the serial of our existing factory fob and I'm about to purchase OBDSTAR F100 or H100. I see instructions/sticky for 'lost all keys' and how to program two new keys, but I'm not clear on if it's possible to simply add a single replacement key (I see add key as an instruction on the OBDSTAR)? Also, I'm not terribly fond of my local dealer so I'm just going to figure this out and give it a go.

Each key fob has an unique ID and as far as I understand you need to go through the dealer to add the key ID to each vehicle after the dealer verified the legit ownership. Not sure about what OBDSTAR can do to add a key fob.

ok, so it sounds like my options are program two new keys or take it to the dealer if the above is true, thanks. If anyone here has experience with OBDSTAR and adding a single key please let me know. Based on reading the sticky it sounds like people are wiping their existing key and re-programming both to match.

https://www.mazdas247.com/forum/showthread.php?123859457-How-to-Mazda-CX-5-all-key-lost

I bought a Mazda key fob on the internet. The price was better than the dealers that I called. I got quotes from several dealers for the programming for the extra key fob and I went with the lowest price. I was told to bring all three fobs and the car to the dealers service center. Everything went well, I got the physical key cut at a local locksmith. Call around for the best price, as dealers prices vary quite a bit.