Assuming this is relatively new - and that your measurements are accurate - take it back - as not suitable for purpose and explain why.
Mine came with a Chrono print out and test target/sheet from the factory - showing 180m/s on three pumps - with Crossman Pointed (7.4 grain) - that's 5.6 to 5.7 FPE... - have you still got the test sheet?
They are adjustable - but it's a hellacious faff.