P0402 Egrc Bpt Valve Issue

[mosilvia]

Hi Engine check light on that P0402.So I checked the Egrc Bpt Valve pressure leak test as showing in the service manual.
I used vacuum pump but it doesn't vacuum (the vacuum pump is not broken).
So this Egrc Bpt Valve needs replace.But this Egrc Bpt Valve has been replaced twice in a year and half.
Is this coincidence? Or is there some other problem?
These two Egrc Bpt Valve are brand new purchasing from Nissan dealer.