My card keeps purchasing for apple.com/bill

Be aware that there are many phishing scams that will also use that as a way to get you to enter your Apple ID and Password. While I do get emails from Apple on subscriptions the I do have, they have never sent me text messages.

To help identify and report phishing scams review this article.

Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

If you do not recognize charges using this support article, then there is also a link to Contact Apple is you are unsure.

If you don't recognize a charge - Apple Support

Does the message show your Apple ID and is your card actually deducting that amount?

If you are getting text messages, then those are not from Apple. You are probably getting scam and phishing text messages. Hopefully, you have not clicked on any link to get to a fake website and entered your credentials. If you have, then ensure that you have changed the password to your Apple ID.

-----

More information below:

All about scams and phishing -

Beware of ➔ Phishing & Other Suspicious Emails 

Know how to Identify legitimate emails from the App Store or iTunes Store 

Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams ➔  Use these tips to avoid scams and learn what to do if you think your Apple ID has been compromised.

Axel F.