Is there such a thing as sincere repentance that is not accepted?

Allah loves repentance, accepts it, and rejoices in it, as His Almighty saying confirms: "And it is He who accepts repentance from His servants and pardons sins, and He knows what you do," and His saying: "Indeed, Allah loves those who repent." It is mentioned in the Hadith that Allah's joy at His servant's repentance is greater than the joy of a man who found his lost riding camel after despairing of it. Therefore, it is wrong to say that Allah does not accept repentance, unless one of its conditions is not met.