Another device on the network is using your computer’s IP address

"Another device on the network is using your computer’s IP address", i've been getting this message on my mac air every day for the past week. it happened once a week or two ago, but now it's daily. Mac air running high sierra. using Airport time capsule 3tb as my internal network

Things i have tried :

renewing the DHCP lease : this doesn't work

Resetting my router. this works, and my laptop uses the SAME IP address it was just telling me it couldn't. but i shouldn't have to reste my router every day.

changing my network to hidden. this works. but then next day i get the dreaded message. i unhide my network, and it allows my ip address again.

I've checked all my other apple devices, the IP addresses are the same they have always been.

can anyone PLEASE help. this is getting frustrating