I have the same issue for about 4 months now. I called apple support and had a 2 hour call where we tried everything. All the basic youtube solutions, all the reset network settings stuff, everything. Nothing worked. At one point they connected me to an IT manager, they pretended they never heard of this issue, and of course, blamed windows. Luckily I already had the same call with windows support, and we tried with them everything too, every network setup is perfect, everything is updated to the latest. After I told this to apple IT guy, they finally took me seriously (after 1 hour or so fighting and telling them, it's not my laptop it's their shit). We just had a new update yesterday, and it is still not solved...unbelievable.