Bismillaah:

Imam Ibn Rajab Al Hanbali رحمه الله reported:

Ka’b ibn Malik رضي الله عنه said:

“Whoever fasts the month of Ramadan and he says to himself that he will return to sinful disobedience when Ramadan is over, his fasting is rejected.”

{ Lataa’if al Ma’aarif 1/222 }

*** And Allaah عزوجل knows best ***