no Free MTX with met conditions Pirate back attachments

did not get the free mtx even after met conditions on twitch and linked account. Still there is no mtx in game. Someone knows how to fix that?

You have to collect them from Twitch first. You should have a notification on Twitch; clicking that should take you to your Drops & Rewards/Inventory page, where you can click the "claim reward" button. If you've already done that, and it still didn't show up in-game, email support -- they're lovely to deal with, and extremely helpful.

If you claimed the mtx on twitch with a linked account click here on your account name go to manage connections and on twitch click the wiew rewards button.

Then the mtx should appear ingame.