what's up,always receive warning

[beinimaliesi]

I'm use examples/langserver_ext.py. when i input ,always receive this warning, and it's not work,editor no response ,i need help

2020-09-22 00:02:28,387 UTC - WARNING - pyls_jsonrpc.endpoint - Received cancel notification for unknown message id 5
2020-09-22 00:02:31,268 UTC - WARNING - pyls_jsonrpc.endpoint - Received cancel notification for unknown message id 11
2020-09-22 00:02:31,271 UTC - WARNING - pyls_jsonrpc.endpoint - Received cancel notification for unknown message id 12
2020-09-22 00:03:00,532 UTC - WARNING - pyls_jsonrpc.endpoint - Received cancel notification for unknown message id 93