The PTCG Live game limits the number of codes that can be redeemed per account. There's a 400 pack limit you can redeem from any particular set (booster pack codes). Any additional codes you redeem give you Coins instead of booster packs.
We suggest that you keep track of the number of codes you have already redeemed before purchasing additional ones.
You can only redeem 10 codes at a time before having to click the redeem button. Be wary of how many codes you input at once or you can get an error.