According to the instructions, approx. 2 years - changing the battery (if you want to do it yourself) is a bit awkward, but there are good youtube instructions on how to do it.
If a repair under warranty is not possible, a cost proposal will first be made, which you can either accept or reject. However, costs may already be incurred for analysing the item.
If the original packaging has been opened, a corresponding discount will be charged for a return. You can find all the information under the following link:
https://www.galaxus.ch/de/wiki/560