Broadband speed was 16Mbps when Plusnet tested but dropped to 1Mbps the next day

[#1]

I switched to Plusnet  at the end of October last year. I had previously had about 14Mbps from BT. The contract did not start very well as I had no phone or broadband for 10 days until an engineer detected my line had been connected to another property. I received an email from Plusnet 14 days after the start date to tell me my download speed was 16.6Mbps. I checked myself and it was 16. Since that date it has been about 1Mbps. I connected my laptop directly to the hub and carried out the BT test giving a download speed of 0.91Mbps. I have not had a very good experience of Plusnet. How do I get my estimated speed of 17Mbps?

[#2]

Sort of begs the question what have you done since October?  Have you completed a fault report have PN advised what the problem might be?
It would help if you could copy and past the results of the BTW test and the further diagnostic test. Please also post the speed at plusnet
see my link below (login required.- do not post you phone number) 
Which router do you have? and do you keep it switched on all the time?
Does your phone work all the time have you tried the quietline test 17070 option2

[#3]

Thanks for replying. I suppose I have suffered the low speed as I only occasionally require the higher speed. I haven't posted a fault report. I have had 2 attempts at online chat, one asked me to reboot my hub and was disconnected, the other seemed to go home at 1700. I gave up after 20 minutes on the phone. My results from the laptop BT test were: Download 0.91,acceptable 4 - 21, IP profile 16.69, upload 1.98, IP profile 0.83. Results from Ookla speed test on my iPad are attached. I have a Sky Hub router that is left switched on.  My phone works OK. I have clicked on your link but could not see where to post any speeds

[#4]

It's the "Current line speed" from https://portal.plus.net/my.html?action=data_transfer_speed we need please.

[#5]

Yes, I should have been more precise.
Is the sky hub just as a wifi access point? I have not found anyone using one as a ADSL router for plusnet as they are usually locked to sky?

[#6]

As you're using a Sky router you're currently connecting with their details instead of ours which will most likely be the cause of the issue.
We'd need you to connect with your Plusnet details but as you're using a Sky router you'll most likely have to get a new one either from us or a 3rd party.

[#7]

I was advised when chatting on line to get a PlusNet router and one is now  on its way