Bank feeds warning and duplicated company credit card accounts

The company credit card number was changed about 7 years ago but bank feeds for the NEW credit card number  (XXX4659) and the closed credit card Number (XXX2297)were matched to the same myob credit account number 2-1120 with no problem. 

All of a sudden, from mid-September, the valid credit card number is no longer associated to the MYOB credit card account 2-1120 any more (with warning).  Based on some post ideas, I created a dummy account 2-1150 so that the bank feeds can be associated to the current credit card number (used for 7 years). Now I have two myob credit accounts for credit cards, one for an expired card number (XXX2297)  and one for a valid card number (XXX4659). 

The problem is: 
with the MYOB dummy credit account 2-1150, I only have about 20 bank feeds. 
with the MYOB credit card account 2-1120, I have millions of bank feeds (mostly approved entries) 

What should I do now?