The debugger does not pause at the next breakpoint and trace doesn't report anything

When I use curl to post a SOAP message into message flow, it takes 9 seconds to respond. Debug won't stop at breakpoints and User Trace doesn't report anything. Meanwhile when I do the same request from Postman or SoapUI (the first message takes the same amount of time, later all messages take around 70 - 200ms) debugger and user trace work as intended. What is cause of this behavior?

IBM App Connect Enterprise 11.0.0.8

curl --trace-time output:

03:29:07.484000 *   Trying <host>...
03:29:07.484000 * TCP_NODELAY set
03:29:07.531000 * Connected to <host_name> (<host>) port 7800 (#0)
03:29:07.531000 > POST /service HTTP/1.1
03:29:07.531000 > Host: <host_name>:7800
03:29:07.531000 > User-Agent: curl/7.55.1
03:29:07.531000 > Accept: */*
03:29:07.531000 > Content-Length: 508
03:29:07.531000 > Content-Type: application/x-www-form-urlencoded
03:29:07.531000 >
03:29:07.546000 * upload completely sent off: 508 out of 508 bytes
03:29:16.671000 < HTTP/1.1 200 OK
03:29:16.671000 < Cache-Control:  no-cache
03:29:16.671000 < Pragma:  no-cache
03:29:16.687000 < Expires:  -1
03:29:16.687000 < X-AspNet-Version:  4.0.30319
03:29:16.687000 < X-Powered-By:  ASP.NET
03:29:16.687000 < Date:  Fri, 22 May 2020 01:29:14 GMT
03:29:16.687000 < Content-Type: text/xml; charset=utf-8
03:29:16.703000 < Server: IBM App Connect Enterprise
03:29:16.703000 < Content-Length: 243

EDIT: I'm still trying to resolve the problem - this time with help of Wireshark and user trace:

curl:

02:56:37.781000 > POST /service HTTP/1.1

after few milliseconds Wireshark detects POST message from "curl machine" - that means there are no problems with the connection

after around 10s delay SoapInput receives data. Why it takes so long?

2020-05-23 02:56:37.257076     6220  UserTrace   BIP11304I: The Parser of type 'MQROOT' has been deleted from address '0x131f1312190'. This thread now has '0' cached parsers. 
2020-05-23 02:56:40.591580     3684  UserTrace   BIP11303I: A Parser of type 'MQROOT' has been created at address '0x131f13144a0'. This thread now has '36' cached parsers. 
2020-05-23 02:56:45.143380     3684  UserTrace   BIP11501I: Received data from input node 'SOAP Input'. 
The input node 'SOAP Input' has received data and has propagated it to the message flow 'link'. 
2020-05-23 02:56:45.143880     3684  UserTrace   BIP6060I: Node 'link.SOAP Input' used parser type 'Properties' to process a portion of the incoming message of length '0' bytes beginning at offset '0'.

Solution

Fixed by restarting the machine. Any clue what exactly caused this problem?