So me and my friend used to be able to connect to a lan world, but for some reason we cant anymore, this has been happening for like a year+. -same wifi -opened to lan -same version We have even disabled both firewalls and it still wont work. Keep in ming that this has been going on ever since he got a new laptop.
If this is a custom LAN world, then make a copy and try to join that. If that doesn't work, then try deleting minecraft and doing it again. If it isn't already in progress, then delete it, and create a new one, and then power on/power off both devices and turn them on again.