3000 Raw files lost!

Of course, I'm to blame! Without backup, it is not easy. I have this card inserted (after successful initial trials) on my trip to Greenland this summer. I take pictures with a new Nikon D800 whose Raw files need a lot of space (40-50 per MB).
My choice was the Lexar not least because of their "lifetime warranty" and the known good service in an emergency.
3,000 Raw files have on the map in the running of two weeks found that were always accessible.
When loading on the PC then an error has occurred and from the card could not be read.
Unfortunately, the map also from (well tried) Lexar Europe service could not be restored.
I then have a specialized laboratory in the UK also commissioned with negative results. The data is irretrievably destroyed.
The (self-evident) offer Lexar may replace the card now, unfortunately, not comfort. That's when a card to more than 300 euros but more than disappointing. I will certainly use a map of this size more. But as mentioned: Without Backup is not possible!