Incorrectly adding up sub-total

[Guest]

Hello,

I have been having a problem that has been bugging me for ages.

It seems that some times when a customer places and order sometimes it over charges. It seems that it only happens every 5 orders or so.

 

eg

 

26.99

10.00

14.95

13.95

sub total - 123.78

 

but it should be 65.89?

 

I have gone into it and placed the exact same order and mine works fine.

Any have any ideas? Or point me in the right direction???

 

Thanks in advance

[♥Monika in Germany]

if you are using default code for calculating your subtotal, this should not happen. a screenshot would be really helpful, as it seems so uncommon that you should be seeing a miscalculation like that ...