@Sunshine Thanks for your reply have deleted all off line Clients, they have not appeared in the online clients, there are various example Ring doorbell, samsung tablet, various Kasa plugs Kp115 and...

Just setup Deco S7 AC1900 x 3 turned WiFi off on my router, but still have many clients off line 42 online across all 3 Deco's 37 off line. I have reset router and reset all Deco's. Have changed...