Calibre not recognising my Kindle Fire

Hi there, I hope someone can help me, I have used Calibre for many years with no problems until I had to get a new laptop as my old one died.
My new laptop is running Windows 10 and since I downloaded the Calibre program onto it - Calibre is not recognising my Kindle Fire, which I have had since Christmas. I had no issues with my old PC and this is driving me nuts as I read approx. 5 - 7 books a week, due to having a chronic back problem and suffering from insomnia.
Can anyone help and point me in the direction of solving my problem?
With thanks