Because NetSuite allows for the Amount field on transactions to be overridden, care must be taken to maintain integrity using one of the two options below.

First Option: If you do not need to see the Amount field exclude it from your template.

Second Option: If you do need to see the Amount field know that if you change quantity or price you must also change the Amount value. This can be done with a formula (Quantity * Price) or manually.

If you do not follow one of the above options you will be able to successfully update the record but the Amount field may be inaccurate.  You will, however, get a yellow notification in the (Reserved) column on the CloudExtend template returning the warning value from NetSuite which is typical