When it comes to canceling a dinner invitation with someone, honesty and respect are key. While it's essential to be genuine and considerate, you might not always need to disclose all the details of your reason. Here are some polite and acceptable excuses you can use:
Prior commitment: You can say that you have a prior commitment or engagement that you forgot about and can't reschedule.
Feeling unwell: Mention that you're feeling under the weather, and you wouldn't want to risk getting anyone else sick.
Family emergency: You can explain that there has been an unexpected family matter that needs your immediate attention.
Work-related obligations: Inform them that something urgent has come up at work, and you must attend to it.
Personal obligations: You can mention some personal obligations that you need to address and can't postpone.
Travel plans: If you have to travel or there's an unexpected trip that you need to take, it's a reasonable excuse.
Rescheduling conflict: Say that something has come up on the same day or time, which makes it impossible to have dinner.
Remember that canceling should be done with sincerity, and if possible, try to reschedule for a later date. Additionally, being prompt and letting the person know as soon as possible gives them more time to make alternative plans if needed. Lastly, avoid using the same excuse repeatedly, as it might come across as insincere if you cancel multiple times with the same reason.