Have you calculated your MPG?
dont go by the dash. not to say its wrong, but its always good to double check if your trying to chase down a possible problem.
rough math....
you say you fill up with 19-21 gallons. ill average at 20 gallons.
250-225 range (per computer). ill use the average of 238 mile range. since i hope you fill up before you run out of gas, ill subtract about 30 miles from the range as the actual miles traveled.
that means your getting 208/20 = 10.4 MPG. seems low.
I drive a short 7 miles commute each way to work, and around town. I get 15.5mpg per the computer. i just took a road trip and average 20mpg. my computer says my range is about 350-375 miles per tank.
next time you fill up (actually 2 fill ups), calculate your mpg the old school way. i certainly hope and assume you know how, but just in case.....
1. fill up, stop at the click. do not top off/overfill.
2. note the mileage on the odometer.
3. drive for at least half a tank under normal conditions.
4. fill up. again, stopping at the click. note how many gallons you added.
5. note the mileage on the odometer.
subtract the miles in step 2 from step 5.
divide that number by the gallons from step 4.
also, after you calculate your actual MPG (you dont want to add any variable in the mean time), use BG 44K. its is a excellent fuel system cleaner...not just snake oil. add 1 bottle per tank, once a year. add it just before fill up. its actually part of the Land rover service schedule that im sure gets overlooked by most.
https://www.amazon.com/BG-44K-Fuel-System-Cleaner/dp/B07GT8RN6Z