How do i cancel my subscriptions when my phone was stolen

My iphone was stolen 3 months ago ,

i could not access my apple account because it sent a verification code to the stolen phone , and thereafter to the number that was in the phone .

I still get billed for my itunes subscriptions even though i turned the lost mode on my phone , and have done the sim swap .

i can now access my apple details from my PC ,

but in the settings option , it does not give me an option to cancel anything .

It only shows me how to cancel from my Iphone ,which was stolen. PLEASE HELP.