ANSWER:
There is no repentance without remorse.
Generally speaking, not everyone feels feelings of guilt when committing a sin. When someone increases themselves in disobedience to Allah azza wa jal, their hearts can become sealed or covered to the extent, that they don’t even feel what they are doing is sinful.
Iman increases with obedience and decreases with disobedience, therefore, you must strive to increase your knowledge about the deen in order to be able to identify sins and repent for them.