A General Dynamics selloff hasn’t improved working conditions at Medicare call centers, workers allege, as House appropriators give the 10-year contract closer scrutiny.

Under new manager Maximus Inc., workers at a Virginia call center aren’t receiving adequate wages, in violation of the federal service contract law, the Communications Workers of America allege in a complaint filed Jan. 31 with the Labor Department. The complaint, viewed by Bloomberg Law March 8, is the latest in a series of wage and working...