Hertz - How do you use the free rental day cert?

I had a biz account and just got two free-day cert. When I tried to use them with the CDP# and PC# showed on the cert online, it always said "Not all requirements for the Promotion Coupon - XXXXX and NPP combination requested have been met"

I do have multiple accounts with Hertz, but I think per T&C on that cert, as long as you have the CDP# and the pc# it should work, since they are charging based on the CDP# rate anyway. But I tried it on all my accounts, neither worked. Do I have to input any rate code or something else?

The other issue is, there are two-free day certificates, but sharing the same pc#, will that take 2 days off automatically if it's working? I need to rent a car for about 3 days.

Thanks.

Anyone please? At least help me figure out which I did wrong. Looks straightforward, but I just could not get it work.

IME, you have to call to make the certificate reservations - I couldn't get the Hertz website to take one either.

IME, you have to call to make the certificate reservations - I couldn't get the Hertz website to take one either.

Are you sure it's always like this? It says call or go to www.hertz.com/smallbusiness. But anyway, I'm trying to sweeten the deal by booking online with some CP to get a free weekend day etc at Orlando, since I have 3 days to go but only 2 free-day certificate. Anyone has experience doing the combo deal? Thanks