If you notice my earlier posts, some of the postcards were stamped in the front so it left ink marks in the beautiful postcards. I thought of just leaving it like that but then I read from a post in the Postcrossing Philippines group in Facebook that you can remove it by using cotton and alcohol or nail police remover. I tried using alcohol and here is the result! There are still ink left but it's not as visible as before.
Anyway, I also asked the postman to tell those who receive my postcards to put the stamp at the back so as not to 'damage' the picture. I think that's a better resolution. My next batch of postcards arrived last Thursday and all of them were stamped in the back. Very good!