2012 Volkswagen Gli Tried Remove Small Dent On Hood Car Using Rubber Puller

I tried to remove a small dent on the hood of my car using a rubber dent puller. After I used it, I notice that when it rains a circle is noticeable where I used the dent puller. I did not dent the metal( it is flat). The water forms a circle where I used the dent puller. I wanted to know what I can do to get rid of this circle. It is not noticable when the car is dry, although if there is dirt on the car it seems to lightly form the circle pattern. Thank You