photo does not meet quality standards

First:

1. The image's histogram shows missing blacks and whites:
   
2. you should add geometry corrections for the building:
   
3. That black column should go away.
4. Correct framing:
   

Second:

1. There is a huge vignetting, especially good visible in the sky.
2. The image is underexposed, as shown with the histogram:
   
3. There is little detail left in the image, probably because of aggressive noise reduction.

I peeked into the EXIF data, so I can say that the camera and lens you used is absolutely capable of taking such pictures, but you need a tripod. I always have a tripod with me. If there is no wind, even a light one is working. Set the ISO at 100, aperture somewhere around 8, the exposure time accordingly to what the camera proposes and use bracketing (I'm using 7 brackets of one stop each). Check the histogram for exposure. You should have at least one picture correctly exposed with that system. It's not necessarily the picture you will choose, but the chances to have a correct one to edit are excellent with that. And if needed, you can do a composite, taking the sky from one and the rest from a second.

Third:

It's slightly underexposed, but that is probably not the refusal reason. I would correct the shadows a little, expand the whites. And I would give the picture a punch of sharpening and structure (clarity, texture). You absolutely need to edit that cable out, and you should also take care of the cables in the lower-left corner.

The H&M sign triggers an IP violation. That must go. As for the "Volkskaffee und Speisehallen Gesellschaft", that could also trigger an IP as the moderator not necessarily reads German and cannot be sure to have here the historic business sign with historic value.

My last critique in this picture is the perspective in which the picture is taken. I think you should have straightened the lines.

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1. Composition must be perfect. There is a huge black element at the side of the picture.

2. Too dark.

3. I don't know about quality but there is an IP violation (H&M would sue). Also composition, the customer does not need photos with power cables in the air.