GST adding to purchases

Hi 

I have just updated MYOB and now when I enter the amount for my purchase invoice into the amount column when the tax code is GST it is adding the GST onto the amount.  Previously the GST would be included in the amount.

For example I would previously put the amount of $341.11 into the amount column and the tax would be GST the sub total would come up as $341.11 the tax as $31.28 and the total amount as $341.11.

Now when I put $341.11 into the amount with the tax code GST the amount in the sub total comes up as $341.11 the tax amount as $34.11 and the total amount $375.22.

I would like it to already include the GST in the total amount as per the first example.

Can you please advise?

Thanks