How to Sum same values

How to Sum with same values using vlookup and importrange

Sheet 1

Rey 1200Rey 700Dan 500Dan 1200

Sheet 2

Rey 1200 (it s/b 1900)Dan 500 (it s/b 1700)

using vlookup & importrange the first row always get the value and i try it with SUM(IFERROR(VLOOKUP(IMPORTRANGE

nothing sees to work