How to make "gpg --card-status" forget an old card

[Arthur Ulfeldt]

I got a new Yubikee Neo and loaded my encryption key to it and
generated new signing and authentication keys. everytime I try to
decrypt a file using the new key, it asks me to insert the old key.
(which i don't have here).

When I run gpg --card-status I see that it still associates the key
with the old key:


~ » gpg --card-status

                 arthur at a:13:32:50

Reader ...........: 1050:0111:X:0
Application ID ...: D2760001240102000006036346220000
Version ..........: 2.0
Manufacturer .....: Yubico
Serial number ....: 03634622
Name of cardholder: Arthur Ulfeldt
Language prefs ...: [not set]
Sex ..............: unspecified
URL of public key : https://arthur.ulfeldt.com/static/B50A93EA.asc
Login data .......: [not set]
Signature PIN ....: forced
Key attributes ...: rsa2048 rsa2048 rsa2048
Max. PIN lengths .: 127 127 127
PIN retry counter : 3 3 3
Signature counter : 17
Signature key ....: 45CA 8D38 F583 E3B3 DAB4  A72C 7119 B2CA 9829 2DD1
      created ....: 2015-09-10 23:03:19
Encryption key....: 342C F561 976F 6DC0 5DD1  CC34 CFED 512B 6EE4 E07A
      created ....: 2015-08-13 08:24:46
Authentication key: C92B 7FEE FDC4 C27A 4F80  E1E5 1CA6 9467 7CCF 8B90
      created ....: 2015-08-18 07:35:01
General key info..: sub  rsa2048/98292DD1 2015-09-10 Arthur Ulfeldt
<arthur at ulfeldt.com>
sec#  rsa3072/B50A93EA  created: 2015-08-13  expires: 2018-08-12
ssb>  rsa2048/6EE4E07A  created: 2015-08-13  expires: 2018-08-12
                        card-no: 0000 00000001
ssb>  rsa2048/BC4C4B6C  created: 2015-08-13  expires: 2018-08-12
                        card-no: 0000 00000001
ssb>  rsa2048/67E40B89  created: 2015-08-13  expires: 2018-08-12
                        card-no: 0000 00000001
ssb#  rsa2048/91FF2F99  created: 2015-08-16  expires: 2018-08-15
ssb#  rsa2048/3157DA5D  created: 2015-08-16  expires: 2018-08-15
ssb>  rsa2048/EADB1671  created: 2015-08-18  expires: 2018-08-17
                        card-no: 0006 03634622
ssb>  rsa2048/7CCF8B90  created: 2015-08-18  expires: 2018-08-17
                        card-no: 0006 03634622
ssb>  rsa2048/98292DD1  created: 2015-09-10  expires: 2018-09-09
                        card-no: 0006 03634622


I'd like to know how to make gpg forget about the old cards keys