What is this Apple services charge of 5,99 every two weeks????

Look at your subscriptions to see what it is. Could be an app subscription. We wouldn’t be able to tell you on here. This is a user forum. But your subscriptions should tell you about any reoccurring charges billing through Apple. https://support.apple.com/en-us/HT202039

Where are you seeing this charge? Also, see this for accessing your purchases, See your purchase history for the App Store or iTunes Store - Apple Support

And see this for checking to see if you have a recurring subscription. View, change, or cancel your subscriptions - Apple Support

This might help as well, If you see apple.com/bill, itunes.com/bill, or an unfamiliar charge on your statement - Apple Support