DIY Electronics service non existent

Purchased a 3d printer motherboard from them..Was delivered 5th Jan 2021. The board is faulty. I have vast knowledge and experience with most makes of printers and boards and am certain there's an issue with the one I bought. It doesn't work at all, not just a small problem.

I notified them the same day and they said they would speak to their suppliers and get back to me. Since then (a week), I've had no response from them despite sending 3 emails on 3 different days.

I called this morn and spoke to a lady who assured me she would get the revelent person to contact me but alas..

Such a pity because up to now I've had good service, although never had to return anything. Its not that I want a refund, I just want a working product!!! Its an "out of box failure", replace it and you take it up with your supplier. Why must I go through this

I'll have to purchase elsewhere from now on