You may not make a retirement coverage election if your qualifying retirement coverage error was previously corrected to FERS, and you later received one of the following TSP withdrawals:
A TSP annuity after separation from service, but before receiving a FERS annuity; or
A single payment or monthly payments after separation from service; or
An age-based in-service withdrawal.
If you received an automatic cashout of your TSP account after you separated (because your account balance was $3,500 or less), or if you received a financial hardship in-service withdrawal, you may make a retirement coverage election.