WiFi speed

When I boot into safe mode and run a speed test using speedtest.net, I get a response of 250Mb. This is what I expect.

When I boot into normal mode and run a speed test using speedtest.net, I get a response of 50 - 60Mb. This is NOT what I expect.

How can I determine what I causing my problem?

I've scanned my device using Malwarebytes for mac

I've scanned my device using MacClean

I've worked with apple support and have gotten nowhere.

I'm running High Sierra version 10.13.4

I do have a vpn software on my system but when I run the speed tests, the vpn software is not running. The VPN is called NordVPN.

Thank you