@Filippo__IT
On my iPad, I would go Settings/Safari/Advanced/Website Data and let it populate.
Then, in the Search box there, I would type Now, and delete the cache data for any entry that looked like Now TV, ignoring false positives like isitdownrightnow.
Then I would try Now in Safari again, bearing in mind that I would probably have to answer the cookies questions once more, and login again, though I would expect it to remember my login.
Bearing in mind you are on a Mac, not an iPad, I would expect the above procedure to be slightly different, but very close to what you do on an iPad.
Set a Payment PIN on your account so that no-one but you can buy memberships on it.
Check your bank accounts monthly for any other unexpected payments to Now.
That way you can at least nip them in the bud, while you and Now figure out whose fault they are.
