IP Profile Set Extremely Low

[#1]

Hi, the last few days have saw our broadband speed drop from around 6MB to 0.3MB. We have tried two routers which were both the same, so I checked on the bt speedtest website and our IP profile has been reduced to 350kbps.
I was wondering if there is anyway for plusnet to increase this manually, as I believe it has been reduced due to the old router playing up wirelessly, and having to be rebooted numerous times this week, obviously causing the connection to drop out.
If it cannot be changed manually how long should we be expecting to wait until the broadband is back up to speed, and 0.3MB is ridiculously slow compared to 6MB.
Thanks

[#2]

Assuming your sync speed has now recovered the IP profile should automatically increase in 2 to 3 days. However leaving the router on 24x7 would be best so the DLM sees that the line is stable.
What are your router stats now (sync speed, noise margin and attenuation)?