Your application has been successfully using a DynamoDB table for over a year without throttling issues, thanks to appropriately provisioned Read Capacity Units (RCUs) and Write Capacity Units (WCUs). Recently, you have introduced a secondary query type that necessitated the creation of a Local Secondary Index (LSI) and a Global Secondary Index (GSI) on a new table to meet this need. However, a month after implementing these indexes, the table is now experiencing throttling.

Upon examining the table's metrics, you can see that the provisioned RCU and WCU levels are still adequate. What could be causing the throttling?