I've been paying $9.99 USD per month for years. A few weeks ago Lightroom went crazy, said I needed to reregister, it couldn't find my license, etc. Eventually I got it working. And now I'm suddenly paying $10.59 per month instead of $9.99 as I have been for years.
There is the possibility that the tax laws changed for your location, and now Adobe must collect sales tax on the subscription. This is an issue you will have to contact Adobe about. We are all just users like yourself and have no connection with Adobe. I live in the state of Utah, and I know Adobe must collect sales tax in this state.