I have never tried a credit card but I find a lice comb provides excellent results. I start by spraying C22 solvent and then put a few drops of exfoliating shampoo on top of the C22. I then scrap excess glue out with a lice comb. This method takes me five minutes and then I rince my hair 3 times with exfoliating shampoo and then a specialist shampoo. It works a treat.
Hopes this helps.
Best Wishes
Deano59