Natural examples:

1. I have an obligation to follow the rules. (daily/business)
私にはルールに従う義務があります。
2. We have a legal obligation to report it. (business)
私たちにはそれを報告する法的義務があります。
3. You’re under no obligation to accept the offer. (business)
その申し出を受ける義務はありません

Nuance

* obligation: A requirement or responsibility that you are expected or required to fulfill. Often used for legal, contractual, financial, or social duties.
* duty: Emphasizes a responsibility arising from your role, position, or moral principles.
* commitment: Emphasizes a promise or personal dedication, rather than something imposed on you.

Expression Vocabulary