Did your phone use 4G or rout through the router during the upload?
When this happens to me, it's either that the PC's wi-fi device is dying or my Verizon router's antenna circuitry is giving out. I have a box full full of both.
MSI Z370 Gaming M5
MSI GeForce GTX 1080 Gaming X 8GB
G.Skill Flare X 16GB 2 x 8GB DDR4-3200 PC4-25600 CL14 Dual Channel
Samsung 960 EVO 500GB MLC V-NAND PCIe Gen 3 x4 NVMe M.2 2280 Internal SSD
Samsung 970 Pro 512GB MLC NAND M.2 2280 PCIe NVMe 3.0 x4 Internal Solid State Drive
EVGA SuperNOVA 1000P2 1000 Watt 80 Plus Platinum Modular ATX Power Supply
Corsair ML120 Pro White LED Magnetic Levitation 120mm Case Fan
Corsair ML120 Magnetic Levitation 120mm Case Fan
Corsair Vengeance C70
Linux Mint Cinnamon 19.0
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