2 Rivens Stolen, only 1 gotten back

[Noah000]

My Kuva Lich took two of my rivens from sorties but when I killed it I only got 1 back despite the result screen showing 2. I thought it could be because one was a rifle and the other was a pistol but when I searched the keyword "riven" in the mods section only 1 riven came up.

[Xikto]

Exactly the same thing happened to me i contacted support and after giving the details [DE]Kenneth told me :

Hello Xikto,

Thank you for that information.

Upon further investigation, I found that you have been taxed 1 Rifle Riven mod on December 18 at 13:09 GMT, and then another Rifle Riven mod on December 20 at 05:43 GMT,.

I can confirm that on December 20 at 06:27 GMT, your Kuva Lich only returned one Riven mod, which has now been unveiled as a Riven for Lanka.

This is not intended and we ask that you report this bug to the Warframe PC Bug Forums.

For this specific instance only, we have added 1 Rifle Riven mod to your account.

Do not forget to report this bug.

Thank you." 

so if u didn't get yours back u can contact the support.