3 Night Panoramic with Mavic 3 Classic.

[Shuttersky597]

Is there a way to avoid the curve? Also original looked so much better.View attachment DJI_0017 res 3.JPG

 

[PanoVolo]

it's a result of equirectangular aka spherical projection. Generally lines will appear as curves in most projections.

 

[Meta4]

Is there a way to avoid the curve?

Understanding how stitched panoramas work can help to avoid compositions that are always going to come out like that.
Smaller sections will work better than such a large span.
This example is showing about 90°

Also original looked so much better.

Much of the problem is that the image is made of small, brightly lit parts in a larger dark area.
The camera cannot give you proper exposure for the dark parts of the image at the same time as the bright sections.
Your eye does it better than cameras can.
For good night photography, look for a scene where more of the scene is lit rather than just a few small, bright spots.

 

[PanoVolo]

for 90 deg rectilinear projection can be used that will keep straight lines straight.