Siren wont stop!

Please can someone help me asap
I have avast anyi theft on my phone tried to add a new sim card to my phone,then siren starts going off
I tried reattimg but dont have wifi or internet & i cant turn the wifi on. Wemt onto my avast avcount and the system was not ajowing my latest phone on there so i couldnt remotely deactivate the alarm. Been ringing avast all day no helpful response. I tried to deactivate it by text prompts that didnt work. I swear i have the correct code but it jus aint working. Please someone help me ASAP

https://www.avast.com/faq.php?article=AVKB214