@Barney9 there are many possible reasons but first using a mobile phone check there is a decent signal in the area near the PC. Next check you are entering the correct password it is very easy to mistake a number for a letter. If you are certain you are and a reboot of the computer doesnt help try updating the drivers.
If still stuck pleaee includecsome details including what OS is runjing and the makecand model of the wifi card.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
