The most common reason that you receive an unrecognised charge from Amazon is that your yearly subscription to Amazon has auto-renewed. Normally, Amazon will charge you £79. If you weren’t expecting this charge then we would suggest that you check your Amazon account and contact their Customer Service department to discuss it further.
Alternatively, if you have seen a charge for £7.99 from Amazon, this is likely because you have signed up to Amazon Prime when making a purchase with Amazon. Normally, the charge will occur around 30 days after your Amazon purchase - you can check your Starling statement to see if the dates align. Again, if you weren’t expecting this charge then we would suggest that you check your Amazon account and discuss with Amazon how to cancel any further charges.