Minor Bug with negative amounts

Hi, I am having problem with negative balance using Tera Wallet. For example if a Customer is -$1000 in the balance, an he creates a new order for $10000, at the check-out the amount to be payed is only $10000 an not $11000($10000 New order + $1000 negative balance)
Any ideas on how to fix this???
I believe It should add the negative amount to the check-out automatically or not?

Best Regards
ED

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