Amazon S3 Issues

Hello, I wonder if I could get some help for a pending AWS S3 issue. I am on a free tier subscription which is meant to end on the 30th of November ( Two days' time). So Amazon has been sending me emails to terminate all pending services within my subscription to avoid being charged for service usage after the expiration date.

The issue, however, is that when I check billing, I can find services connected to S3 buckets, but when I check for buckets in my environment, I cannot find any buckets. I have reported this to Amazon and they are suggesting they are perhaps API requests. Now I am very new to AWS services so not very conversant with where to look or what I am supposed to do to terminate all these services and tools.

Therefore, could anyone please help explain exactly what i am supposed to do to terminate all services or sub-service or tools within my Amazon environment to avoid being charged?

I have attached a copy of my billing and S3 environments. Regards K David