It was narrated from Ibn 'Umar and 'Aishah that the Messenger of Allah (ﷺ) said:
"Whoever demands his rights let him do so in a decent manner as much as he can." (RU)
English reference (RU): Vol. 3, Book 15, Hadith 2421 (RU)
Arabic reference (RU): Book 15, Hadith 2515 (RU)