How can I detect cell phone spyware?

How can I detect if someone has implanted spyware on my cell phone? About 1-2 months ago, for a couple of hours every time I called someone in the call log it would have that call and the cal to some random numbers I didn’t recognize. How can I detect if someone put a spyware of or some other way of tracking listening to my calls?

Use legacy cell phones, and you are free of spyware and viruses