TurboTax should automatically pull both employer's contributions into the Let's enter your HSA contributions screen. Are both employers' contributions on their respective W-2s have Code W in Box 12 with the contribution amount?
If you are married, make sure that both W-2s are in your name, not your spouse's. Also, make sure that after you enter the W-2, you answer No to Did any of your HSA contributions go into your spouse's account?
If neither of those are causing the problem, and the contributions still aren't feeding through to your HSA screens, you may need to delete the W-2 containing the contribution that did not go through and re-enter it. If you imported it the first time, you may need to type it in manually. Make sure Box 12 has Code W for your employer's HSA contributions.
