From Sahih Bukhari (Hadith 2609):
Narrated Abu Huraira:The Prophet (ﷺ) took a camel of special age from somebody on credit. Its owner came and demanded it back (harshly). The Prophet (ﷺ) said, "No doubt, he who has a right, can demand it." Then the Prophet (ﷺ) gave him an older camel than his camel and said, "The best amongst you is he who repays his debts in the most handsome way
Reference: Bukhari 2609