I’m not able to cancel a subscription, I don’t want it. I tried to log in But system won’t take my password

contact iTunes Support. See the Apple Support articles below for contact information.   

iTunes Support – world wide 

Apple Support schedule phone call       

Several people have posted that they have the same problem. Apple may be having problems with the server. There was a post 2 days ago that someone who had spoken to Apple Support was told that the servers were undergoing extensive maintenance. It is not a solution, but try again tomorrow.

Do you have access to another WiFi network where you can try? That has worked for several people.

Try a restart.

Restart your iPhone, iPad, or iPod touch         

Try a forced restart.

Reset Device.      

If necessary

Hard reset.        

Do a backup and try a factory reset. Then restore from your backup.

Restore to Factory setting.      

Backup - Restore your device from an iCloud or iTunes backup.