|The wireless mouse and wireless keyboard probably do not communicate with each other. |
If they were bundled together, they use the same USB transmitter - receiver to communicate with the computer.
If they were NOT bundled together, they may or may not be able to use the same USB transmitter - receiver to communicate with the computer.
You may need to change the battery(ies) in the mouse as well, and or follow some procedure to activate it.
Modern more inexpensive keyboards do not last as long as modern more expensive or older keyboards. After you have used the keyboard a lot, eventually, it`s likely the keys you use most tend to become unreliable If the keys that are unreliable do work when you press them harder, other keys work fine, that has nothing to with any software or wireless signal strength problem.