Had to go around the system, but I got our reservation for 3.
Initially nothing came up, but when I put in party of 5, lots of times popped open. After I booked, I went in to change my reservation. I reduced party to 3 and a new time for lunch came open 15 minutes earlier than my party of 5 reservation. Switched it easy peasy.
OP, try increasing party size and changing it after you book. If you cannot alter it, then just cancel the reservation if you feel uncomfortable.
Good luck!
Thank you for this. I have been trying to get a reservation for 2 on 8/8 for lunch since they opened up ADRs and was able to do it by reserving for 6 and then changing it down 2 after.