Diagnosis
The water inlet valve screen is clogged with sediment, or the dispenser itself has a frozen line. The valve screen is the first check.
How to Fix It
Clean the inlet valve filter screen.
1. Turn off the water supply to the fridge at the shut-off valve (usually under the sink or behind the fridge).
2. Unplug the fridge. Pull it out to access the back, bottom-left corner.
3. Locate the water inlet valve (a plastic unit with multiple tubes/connectors). Disconnect the water supply line from the valve.
4. Use needle-nose pliers to gently pull out the small plastic filter screen from the valve's inlet port. Rinse it under warm water to remove sediment.
5. Reinsert the screen, reconnect the line, turn water back on slowly, check for leaks, and plug the fridge in. Test the dispenser.
If That Didn't Work
The water dispenser line running through the door may have a partial freeze-up, common if your freezer is set very cold. Unplug the fridge for a few hours to let it thaw completely, then set freezer to 0°F, not lower.
Heads Up
Always use a genuine or Samsung-approved water filter. Some third-party filters can restrict flow more than intended. Also, after changing the filter, run 2-3 gallons of water through the dispenser to purge air from the system, which also causes slow flow initially.