Happened to me before when I try to redeem Uplay passport code for Assassin's Creed Revelations (R1). The problem is this code from R1 game not compatible with my PSN account and PS3 consoles (both R3), which was what I told by Ubisoft Support when I try to argue my case.    Perhaps the same case happened to you as well.

It's not console problem, should be PSN account region and game region. Normally, DLC and voucher code are locked to region, you can't redeem R2 DLC and voucher code using other region PSN account (like R1 or R3), it MUST redeem under R2 PSN account.

I think you created your PSN account using Malaysia address, right? If yes, then your current PSN account is R3. So, you can't redeem R2 voucher code.
Normally, we can create R2 PSN account (use fake UK address, google it, you can get fake UK address easily) and redeem the R2 DLC and voucher code using R2 account. After redeemed, change back to main account (R1 or R3) and play the game, the DLC still usable under R1 or R3 account.

But this GOW: Ascension DLC and voucher code a bit different because it tied to account which redeemed it. That's means the DLC items redeemed under R2 account can't use in R1 or R3 account. If you want play with those DLC items, ONLY solution is play the game under R2 account.

You need create NEW account (make sure use UK address), you can't edit current R3 account to R2 because once registered, you can't change country registered.

If you plan collect trophies under MY account, then stick with MY account and play all games using this account. To be safe, better buy game region same as account region in future, so will not encounter DLC and voucher code can't redeem issue.

you need a new account. once you created the malaysia account, that is locked to malaysia. you need a completely seperate R2 account. i just grab addresses of hotels in the UK to set it up.

How to check which region my psn is in?

And do add me...kenari106

Tq