Yey! Finally, I got an answer from support, it seems my purchase of RP was for a rare reason delayed, 11 days, instead of the normal period of 24-48 hours. I was starting to get worried since it was 16.5k RP (
shame on me).
The goods news is that Riot in compensation for the delay, they gift me with some IP boost. (It's free who would complain for getting free stuff?). Now I'm waiting for an answer about me missing the 2x1 rune pages sale due to this delay, hopefully they will manually activate that sale for my account, if that is even possible.
It's the last time I use that method of pay. (Print the code, then pay in a 7-11) I used it because I don't have a credit card. (The disadvantage of debit card, no internet purchases for me, well, not for this specific debit card, whatever). Next time I will be less lazy, and just go and buy a paysafecard. (I would have to go a little further to buy it... like 1.5 minutes of driving.
tl;dr being lazy gets you free IP boost, but you will miss sales, not worth it.