This can happen for several reasons but here is the best way to fix this.
- Whatever your maximum dimension in your pricing table is, increase it to be larger than the maximum you want a user to be able to input.
Example:
Maximum width is 100 and maximum height is 150.
Change the pricing table to be:
Maximum width is 101 and maximum height is 151.
This is just slightly larger than the actual maximum values you want a user to be able to input. - Then on the lookup option, set the maximum for each input to what you really want the maximum to be. This will restrict the input field to the max values that you want.
Example:
Input 1 Maximum 100
Input 2 Maximum 150