Dear @Jeddy,
Welcome back to the Wefugees Community and thank you for reaching out to us again.
As far as I know, there is nothing like an obligation to apply for another residence permit (in this case for the residence permit according to section 28 of the German Residence Act) after the marriage. The immigration office will anyway not simply "change" your residence permit without your prior application. On the other hand, keep in mind that a residence permit as spouse of a German citizen may give you the chance to apply for a permanent residence permit (Niederlassungserlaubnis) already after 3 years. For more information on this follow this link, for instance (describing the process in Berlin though).
I will also link our dear @mbeon-Christine and @mbeon-fardeen here. Do you agree or/and is there anything you would like to add?
In any case, please don't hesitate to get back to us with any further questions.
All the best,
Meike