INCORRECT ACTION IMPLEMENTED BY MWEB FOR MY QUERY

I called MWeb earlier on today, 03/12/2019. I asked for a simple thing to be done - for my uncapped 20mb/h to be reduced to 10mb/h- still uncapped. Now when I try to do some work, I get a message that I have "reached my limit on my capped data" and that I must purchase additional data to top up my data! That is not what I requested! The self-service offer is also not useful! I need this resolved as a matter of great urgency as I need it for my work please. Regards, Sharon