How to resolve neighbour’s noise problem in an apartment? (especially Mannheim)

Hello, I have an issue with my upstairs neighbour's heavy stomping sounds not only in the afternoon. It is also night and midnight.
I read some articles on how to resolve it and then I already tried the list below.
– talk to this neighbour directly
– report to a landlord
– report to a Wohnungseigentumsverwaltung (apartment management office)
– report to an Ordnungs- und Servicedienst Amt -> They said, in Mannheim, Ordnungsamt doesn't handle private noise issue
However, it hasn't been resolved yet.
Is there any idea that we can resolve the issue?
My background is:
– office worker
– I can write simple German sentences (A2 complete level). But it's hard to speak about the very first and most complicated topic.
– looking for a new apartment as well. but as you know, it is hard to find out due to the shortage of apartments in Germany. And also the tenant has a 3 months notification rule. So I need to stay for the time being
I want to know those things as well.
– Is there any official department that can handle private noise issues (especially in Mannheim)? As far as I know, in Berlin, residents can report to Ordnungsamt about private noise issues online (for example https://allaboutberlin.com/guides/noise-complaint ) However, in Mannheim, Ordnungsamt doesn't handle private noise issues.
– Is there any way to report to the police (especially in Mannheim) online? calling is also hard for me.
– Even if a police officer speaks English, could we report the issue that is not happening now? To be honest, I don't have the confidence to explain via telephone. I want to go to the police office and explain the details if there is no method to report online.
If you have any information about it, no matter outside of Mannheim but in Germany, please give me some advice.
Thank you very much for your help.