Gas Pipe Placement for Amica EBR7331AA Built-In Oven: Can it Run Horizontally? Solutions?

Hello,
I have a question. I had a new gas installation in my kitchen. The installation is welded, the vertical part hidden in the wall. The rest of the installation runs from the corner of the kitchen towards the window at a height of 50 cm at a distance of about 2 cm from the wall. An electric built-in oven and gas hob will be installed in the corner of the kitchen. The valve is to be placed in a cabinet under the sink, which is to stand next to the cabinet behind the oven.
These were the previous arrangements, because today I learned that the gas pipe should not run horizontally and adhere to the back wall of the oven. Gentlemen, is that true?
If so, what solutions do you propose? The oven is Amica EBR7331AA.

Thanks in advance!
Dorothy

The person who made the gas installation should know the regulations. The valve cannot be retracted, it should be in an accessible place. Gas pipes do not build up, they should be led upwards and down to the connected receiver.

Thank you for your answer. The valve will be available in a cabinet under the sink. Only the pipe that was supposed to run horizontally behind the cabinet with the oven to the cabinet with the sink, where the valve is to be located. There will also be an Ariston water heater in the cabinet under the sink. Hence the height of 50 cm above the floor. The professional who made the installation had qualifications and apparently did it in accordance with the regulations ... So, however, the gas pipe cannot run behind the oven wall? At a 60 cm worktop and 56 cm deep oven, it comes out that the pipe will adhere to the oven wall. I understand that the pipe will heat up from the oven?