Don't have you vs mustn't

[Viki]

Hi Torsten and Alan!
I need your help
What the difference between
Don't have and Mustn't
Thank you teachers in advance
Viki

[Torsten]

Hi Viki,

You don't have to means you are not obliged to do it. (you can decide yourself if you want to do something or not).

You mustn't means you are not allowed/you have no permission to do something.

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