First sort the total sales in ascending order

Cal $190,000
Dot $210,000
Bob $360,000
Ann $450,000
Ed $680,000

The new median is $330,000. So, either Cal's or Ann's sales will be $330,000.

(1) If Cal's sales is the median, 330,000 - 190,000 = 140,000 --> This is the incorrectly recorded sales value.
Subtract 140,000 from Ann's. 450,000 - 140,000 = 310,000

But in the question, it says that Ann's sales is still greater than Cal's despite the change. So this scenario is ruled out.

(2) If Ann's sales is the median, 450,000 - 330,000 = 120,000 --> This is the incorrectly recorded sales value.
Add 120,000 to Cal's. 190,000 + 120,000 = 310,000. YES - Ann's sales is still greater than Cal's. Condition satisfied.

So, the incorrectly recorded sales value is 120,000