The US Air Force is blocking early retirement for transgender members with 15 to 18 years of service, forcing them out without retirement benefits, according to a recent memo. Those affected must either resign or be discharged with a lump-sum payment, according to BBC.

This move is part of the Trump administration’s transgender military ban, which critics say is unfair and discriminatory. Early retirement remains available for those with 18 to 20 years of service, but full benefits require 20 years.

Over 4,000 transgender troops serve in the military despite legal challenges and changing policies, BBC reported.