Hello and welcome to justanswer, My name is ***** ***** i will be assisting you today,
I am sorry this has happened to you. This is a popular scam that has been going on, Pleas do not call them
Please follow the steps below to unfreeze/speed up/clean your computer :
1. Let's end some of the processes, as that can cause the computer to be slow.
Please click Start, then Run. In the run box, please type msconfig and press enter. click on the Startup tab then click Disable All Click Apply, then OK. You should be prompted to restart your computer, please do so.
2. Next, you want to run Malwarebytes, a free malware/virus scanner. Please click https://www.malwarebytes.org/mwb-download Click Download, Once you install it, Please Update and then run a Scan and Delete any Malware/Viruses. It should take 25-50 minutes to complete.
3. Once that is complete, please download Ccleaner, as this will clean temp and cache and corrupted files from your computer. Click http://www.filehippo.com/download_ccleaner
4.Reset google chrome : https://support.google.com/chrome/answer/3296214?hl=en-GB
Once you run that and delete everything, please let me know if your computer is running faster.
If you have any questions, please reply and I will assist you.