First, I recommend that you check the water level in the bottom of your dishwasher to actually see if you have a water fill problem. The water level in this dishwasher should be at a maximum height of 1/4" above the base of the float dome as shown in the image below. Keep in mind that this is the maximum fill level in the bottom of the dishwasher. This is the point at which the float will lift and stop the water fill. The normal fill level is usually below this point. If you start a cycle and let the dishwasher fill and then crack the door when the filling stops, you can then fully open the door and check the water fill level. If it is close to this maximum level then you do not have a fill problem in the dishwasher.
If the fill level is nowhere close to this level and obviously low, then you can follow these troubleshooting steps:
Make sure that the water cut-off valve for the dishwasher is fully open.
Shut off the breaker
to disconnect power to the dishwasher and shut off the water supply. Reverse the steps in the installation guide to pull the dishwasher out and access the fill line. Here is a link for your installation guide:
in case you need it. You indicated that you checked the fill line but you did not indicate that you verified the water pressure and flow coming from the fill tube. I recommend that you disconnect the fill line and place the end of it in a shallow container. Briefly turn on the water cut-off valve to check for proper water pressure and flow from the fill line.
If water pressure and flow from the fill line is okay, I recommend that you remove the elbow on the bottom of the fill valve and check for a clogged inlet screen. Debris or deposits can clog this inlet screen and inhibit water flow into the dishwasher. If the screen is clogged then cleaning it thoroughly and replacing it in the inlet water valve may resolve a fill problem.
A failed inlet water valve or a problem with the wiring or the control could also prevent the dishwasher from filling properly.
If the dishwasher is apparently filling properly, a problem with water temperature could prevent the package of detergent from dissolving properly. Check the water temperature by running the sink hot tap for 1 minute. Fill a glass with the hot water and check the temperature of the water with an accurate thermometer. It should be about 120 degrees. If not, then I recommend that you adjust your hot water heater.
The Cascade packages may not work properly in this type of dishwasher. I recommend that you try using regular Cascade powder. This may help you resolve your problem.
If you need more help, resubmit your question with additional details.