Let λ
1, λ
2 be positive real numbers such that
({frac{{lambda_1}}{{lambda_2}}}) is irrational and algebraic. For any (
C,
c) well-spaced sequence
({mathcal {V} = {{v_i}}_{i = 1}^infty}) and
δ > 0 let
({E( {mathcal {V},X,delta})}) denote the number of elements
({v in mathcal {V}, v le X}) for which the inequality
$| {lambda_1 p_1 + lambda_2 p_2 - v} | < X^{- delta}$
is not solvable in primes
p 1,
p 2. In this paper it is proved that
$E( {mathcal {V},X,delta}) ll X^{frac{4}{5} + delta + varepsilon}$
for any
({varepsilon > 0}). This result constitutes an improvement upon that of Brüdern, Cook, and Perelli for the range
({frac{2}{{15}} < delta < frac{1}{5}}).