Move your VAIO computer away from obstructions, or closer to any access point you may be using.
Connection capability is affected by distance, obstructions, device configuration, radio wave strength/interference, wall materials, running apps, etc.
If you are using an access point, the device may be temporarily overloaded depending on how many other devices are communicating via the access point.
Wait for a while and try again.
Change the channel setting of your access point. By changing the channel, interference on your wireless network may be reduced and data transfer speed may improve.
If access point channel interference occurs, data transfer speed may be reduced.
If your access point interferes with other access points, change the access point channel.
Refer to the manual that came with your access point for more information.
Make sure that a microwave oven is not operating near your Wi-Fi devices.
The 2.4 GHz frequency band, on which Wi-Fi operates, is used by various devices and apparatus. If you use a microwave oven while communicating via Wi-Fi, data transfer rate may slow down, communication range may narrow, or communication may be interrupted.