Gigablast barely reaching 250mb

Had gigablast installed last Saturday and so far the fastest speeds I can reach is around 250 down. Yes I have bypassed my router and connected straight to the modem with my laptop. Yes my laptop has a capable gig nic card. I’ve also tried another laptop same thing. 3 technicians have shown up to my house and have done speed tests with their handheld devices and tell me they get 940 down. They have changed out the modem and even ran another line to test. Same results. They tell me the speed is fine I show them my laptop speed results hardwired into the modem and they tell me it’s my laptop. Oh yeah forgot to mention this is fiber...... another thing worth mentioning is at my last residence we were getting 300 down over coaxial which is fine because that’s what we were paying for. I was also told by the Cox technicians that this was a “back office issue” what exactly does that mean? I was also told by a Cox tech that “him and his buddy are two of the best techs Cox has in this area” ok great fix my internet speeds. So I’m pretty so after the techs left today they ultimately ended up blaming the speed issue on my laptop and left so I guess that’s that I pay 100$ A month for gig speeds that I don’t even get close to reaching. I’m also a Pc technician with 14 years experience so I know a thing or two about networking and computer hardware. I’m about to cancel Cox and switch to Att and I’ve been a loyal customer with Cox for almost 20 years off and on. Anyone have any ideas on how to fix this issue or have any experience with Att? Their gig internet is half of what Cox is charging. Help me out Cox your gigablast is false advertising!!