Strange behavior; I've been reloading five Mobile Suicas over the past three weeks via Apple Pay- AMEX biz gold for the 4X MR. Try adding an additional Mobile Suica to fund, and/or removing and adding AMEX biz gold to Wallet.
You can use multiple Suicas and other IC cards on Apple Wallet, just keep track of which one you want to use as Express transit and link to ticketless travel on JR.