What could be a cause of slower internet?

[YoungDNL]

Hi, I just received my fibre max from my broadband provider, and i was wondering what the speeds I will get on devices, so I ran a few tests from ookla speedtest and received different results.
On my Phone Samsung Galaxy S7 edge i have received the following:
51.5 Mbps Download speed
18.7 Mbps Uplead speed
24ms
On my PC using a TP-LINK Dongle with 150 mbps range i received the following:
23.16 Mbps Download Speed
18.55 Upload speed
24ms
What could the issue be that im getting twice as much on my phone than on my pc?
I was thinking it could be that im using the TP-LINK modem and should perhaps buy a WiFi booster to plug in and receive better connection. Or is it a system issue?
If you require more info please let me know and i will provide

 

[failboat]

The phone is dual band. they may be on different bands.
wifi speeds are normally limited by the client.
From 10 ft away in direct line of site you only get -50dB or about 5% of the potential speed.
listed wifi speeds are tested in a not even realistic setting. the best you can get is around -30dB with your phone right on the wifi, which is maybe 15-25%.

I'd recommend trying to wire your pc with ethernet.

https://www.smallnetbuilder.com/wireless/wireless-reviews/33084-ubiquiti-ac-pro-and-ac-lite-access-points-reviewed?showall=&start=2