Welcome Spiros!
Sorry to hear about your loss
But don't give up! Many of us loose their aircrafts, it's a part of the learning process.
The Mavic Mini is so small and light, it is very sensitive to winds. So it is very easy to loose it when you fly, because it is so fun and exhilarating
Two things;
1: Is there a "FInd my drone" function in the Fly app? In the Go4 app, there is such a function. Saved my Mavic Pro one time, praise be to DJI.
2: If you don't find it, you could try to post your flight log in the "Crash and flyaway assistance" section of the forum. If you are lucky, one of the geniuses who frequently posts there, might be able to point you in the right direction wherre your Mini went down.