Logitech wireless mice and keyboards are very popular.  Unfortunately, it is very easy to lose the USB dongle (adapter) for wireless mice and/or keyboards.

With keyboards and mice from other manufacturers, that normally means you must order a new USB dongle, or replace the keyboard/mice altogether (assuming they aren’t blue tooth).

Thankfully, Logitech has made it possible to use any Logitech USB dongle with Logitech keyboards/mice.  However, they all must have the with the Unifying symbol on them.

With that though, the Logitech Unifying Software at the following address will allow one to pair a Logitech USB dongle with a Logitech keyboard and/or mouse.:

https://support.logi.com/hc/en-za/articles/360025297913

NOTE:
There will be some instances where an older Logitech wireless mouse and/or keyboard do not pair with newer Logitech dongles, and vice versa.