WordPress cannot access web server

Hi there, can anyone help me please. I have recently changed my hosting package and now when I want to update my plugins I get the following message:
“To perform the requested action, WordPress needs to access your web server. Please enter your FTP credentials to proceed. If you do not remember your credentials, you should contact your web host.”
I spoke to UK2 my service provider and they said that I may have to remove the ftp details from the wp-config.php file. Is that correct? And how do I do that?
Thank you very much in advance,
Elke