According to the official fee documentation:
When network activity is below capacity, you pay the network minimum, which is currently 100 stroops (0.00001 XLM) per operation.
However, I found ledger 171583 in the testnet which contains 3 transactions (below the current 50 capacity) each containing a single operation (below the current 100 capacity). However, the fee charged for each transaction is 100000 stroops.
Can you explain the reason for the high fees?