The AXI4ToTL converter depends on having a downstream error device available to bounce non-compliant traffic while preserving AXI ordering semantics without requiring the adapter to have internal state.
The default RocketChip configuration provides such a device here:
But perhaps you have modified the bus architecture significantly? You can add one to any CanHaveBuiltInDevices child class (e.g. any of the TLBusWrappers) using the same argument to the HasBuiltInDeviceParams child case class. You could also add one by hand using this as an example: