Doing x.stop_sequences() is causing this UVM FATAL Item_done() called with no outstanding requests. Each call to item_done() must be paired with a previous call to get_next_item()

In reply to uvm_va_1:

You shoule never stop a sequence. This might cause serious issues.
Any sequence comes to its end and that’s fine. If you are running in any deadlock your sequence execution has to be modified.