6700 Apex Coins won't be redeemed

I play on Steam and I charged my steam wallet with 60$ to buy 6700 coins. Steam charging went smoothly, then Apex won't take the money for 6700 coins! 

I tried buying 500 coins and it worked.. 

and yes I was sure that I had the right amount in my steam wallet before purchasing the 6700 bundle.

So in short, 6700 coins won't do it. While 500 is ok. why?