New fibre speed half what it should be?

[#1]

I had fibre installed 2 weeks ago and had a DL speed of 40M and upload of 2M. Now my DL speed is 21M.
Can someone at Plusnet take a look for me?

[#2]

Downstream Speed 40.0 Mbps
Upstream Speed 2.0 Mbps
Profile Name: 0.128M-40M Downstream, Error Protection Off - 0.128M-2M Upstream, Error Protection Off
Your line is still connected at 40Mbps and the profile is set accordingly on our side, so there shouldn't be any issues.
Are you testing wired or wirelessly? Have you been through the BT speedtester? http://speedtest.btwholesale.com/

[#3]

Yes, it's gone up to 37Mb DL, which is fine. I'm connecting wired and tried the BT speed test earlier and was getting 21Mb.
Seems to be okay now. Thanks.

[#4]

I've switched on Monday and my download speeds have been a little disappointing - usually around 9 or 10Mbps when I was told to expect 'up to' 18Mbps.
I'm hoping that it will improve as on ADSL I was usually getting roughly 2/3 of the promised 'up to' speed which led me to hope I'd get around 12Mbps on fibre.

[#5]

@WTF
Our tests are showing a bridge tap issue which is normally star wiring.
Can you raise a fault here https://faults.plus.net and we'll look into it.