How will miners generate income when all the bitcoins will be generated?

Greetings friends!

According to Bitcoin mining, Bitcoin is mined when the miners are able to generate a block. They get Bitcoin as a reward for their efforts. We know that the amount of maximum generated bitcoin is fixed. In that scenario what will happen when all the Bitcoin will be generated? How will miners generate income? Do you know the answer? If yes, then inform me through your comment.

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