What’s your version of kdeconnect? If it is 1.33.0 on an Android phone, you are probably running into a bug described here: Devices don't see each other after Android app 1.33 update
What’s your version of kdeconnect? If it is 1.33.0 on an Android phone, you are probably running into a bug described here: Devices don't see each other after Android app 1.33 update