Whether to connect the washing machine to the socket through the extension cord!

I bought an Amica washing machine and in the instructions it was written that it is absolutely not allowed to connect the washing machine via the mains adapter. The cable is exactly 1.5 meters and unfortunately I have much further to the socket. I was told that this is a European Union requirement and that all products have this cable length. I am asking you - professionals for help in this matter. Why are there such recommendations and what are the reasons for them!

Hello
for me, this matter is nonsense, and seriously, it is probably that you can connect only through an extension cord in which there are 3 wires, i.e. the one with "pins" and everything should be OK.
Regards

A vacuum cleaner with such a cord would be nice. Amica, like any company, protects itself against everything. Due to the conditions prevailing there, the extension cord in the bathroom is not a very interesting idea. But if you have no choice, what you will do, you will not modify the installation - it is too expensive. Replacing the cord with the plug the risk of losing the warranty (unless the washing machines are not sealed) is the most appropriate way out. Ultimately, it could be a grounded extension cord with one airtight outlet.
Regards.

Ps these are my suggestions, maybe someone will tell you something else. I would be in favor of replacing the cable.
He himself has a washing machine, moreover, Amica on the extension cord in the bathroom - from pure laziness.

An extension cord can be used, but a 2.5 mm2 cable and a properly selected socket, preferably 16A with a ceramic insert, and a 16A plug. So all Chinese extenders like this fall off. Of course, you should protect the socket against water. Therefore, all companies reserve the right not to use extension cords. It is also related to the protection against electric shock.

To what Paweł wrote, I can only add that this cable thickness is due to the power of the washing machine (in total, the heater, which, depending on the type, can be up to 2.5kW).