Recurring appointments are linked in the background, so payment works a little differently. You can only log a payment for one appointment at a time, not the whole series in one go. You'll need Stripe, or the Cash feature active to do this.
Take Payment for Recurring Jobs
Click the relevant appointment in your calendar. In the Appointment Details window, click Edit Appointment.
Make any changes needed, then click Save. You'll be asked whether to update just this appointment or the entire recurring series.
In the appointment window, select Payment, then New Payment.
Fill in the customer's payment details as normal and click Pay.
A "Payment was successful" confirmation will appear once the transaction is complete.