"Hi, my dongle is no longer working, although the mouse is fine. Could you please assist with getting a replacement dongle? If it's possible to purchase one, could you recommend the correct model? Thank you!"

A 36-month / 3-year or 48-month / 4-year warranty refers to the total duration of the warranty from the date of receiving the goods. Compared to standard statutory rights, this gives you an additional 12 months / 1 year or 24 months / 2 years, respectively, to file a claim.
Specifications can be changed without notice. Images are for illustrative purposes only.