SolvedDog Tag Help

I want help in the dogtag everytime i do the 3rd mission i get no new letters! so i did the first and also got no new letters and when i got another S (i already have 1 S) it did not mention it at all and did not count! now what? i am at this for 3 weeks at least!

yes my dog tag not complete i don t know why although i am sure that i completed it

this is screen shot

Report that to Z8Games.........you are Unlucky

yes happeneds to me i need the "F" but they keep giving me the "S"

The dog tag letters are given RANDOMLY. If you get a letter you already have, don't feel cheated. Just think of yourself as...unlucky.