[ic] Purchase Order and credit Limit

[interchange-users@interchange.redhat.com (Andrei Gologan)]

Hallo

I have to build a shop using the purchase order option and credit_limit
The problem is that it does not reduce the credit_limit field in the userdb

In  log_transaction it is:

[if value mv_payment_mode eq purchase_order]
set credit_limit: [seti credit_limit][data
                table=userdb
                col=credit_limit
                key="[data session username]"
                value="-[scratch total_cost]"
                increment=1
        ][/seti]
[/if]

It recognizes when the customer wants to buy more than his credit, but I
also need it to reduce the credit amount after a puchase.

I allready tried the value:
value="[calc][credit_limit]-[scratch total_cost][/calc]"
value="[calc][value credit_limit]-[total_cost noformat=1][/calc]"
value="-[total_cost noformat=1]"

but nothing works the credit_limit does not change.

I hope somone can me the right direction

Thank you
Andrei