There seems to be a difference between the available Store Credit of yours with the site currency you had picked previously. Would you like to:
Fortnite ACCOUNTS USD $135
Fortnite ACCOUNTS USD $54
Fortnite ACCOUNTS USD $119.99
Fortnite ACCOUNTS USD $9.99
Fortnite ACCOUNTS USD $11
Fortnite ACCOUNTS USD $48
Fortnite ACCOUNTS USD $49.99