Welcome to the forums.
Are you certain these Texts are actually from Plusnet? How did you call the operator, hopefully by not pressing a number from the text? Did you contact Plusnet via the contact phone number on the website?
This could be sadly a well known scam still doing the rounds claiming your broadband will be disconnected in 24 hours etc, we have had repeated calls about this but they are not from Plusnet
Thanks for getting in touch @Aljmuir
I can see the order another provider has placed to takeover your line is in the process of being cancelled on the back of your conversation with an adviser on Friday. This should hopefully be sorted within the next 24-48 hours.
I'll check back on Wednesday to make sure that's resolved or to investigate further.