Unable to select MB/Chargepoint partner as preferred charging network

I'm trying to use up my $400 chargepoint credit on a trip from Atlanta to West Palm Beach in Florida.

https://abetterrouteplanner.com/?plan_uuid=2-69faf23f-1220b26e71eaef1f34a6c59c

I have set the mercedes Benz as preferred network. I have put EVgo, flying j, Tesla, electrify America, fpl as networks to avoid. But I still can't get ABRP to stop at MB networks even though I know there are at least 3 on the way at Buckee's.

It's bad enough that I can't filter by 350 or 400kw chargers. What's the trick to get this working? I'd like to stop at MB preferably. And if not available then Ionna.

Thanks.