3385533 - XSA application route not working - No system found for vhost - 503 system not found

After setting up mapping route in XSA application, URL is not reachable and drops:

503 system not found
503 Service Not Available

dev_trace shows:

[...]
Started service PORT=44300,PROT=HTTPS,TIMEOUT=60,PROCTIMEOUT=600,VCLIENT=0,SSLCONFIG=ssl_config_0
[...]
IcrIAddSingleSystem: Added backend system: SID=0IW, NAME=0IW, SRCURL=/toolshed/xsjs, SRCSRV=*:44300, EXTSRV=http://127.0.0.1:50946#<...>, SSL_IGNORE_HOST_MISMATCH=true
[...]
IcrFindTargetSystem: No system found for vhost: <route 2 FQDN> addr: <IP address>:30033 url: /toolshed/xsjs/index.xsjs
[...]

xscontroller_0.log shows:

[...]
[Controller.Route]-[log]-[1584939]-[unmap-route (7915) - 1407469]: Unmapped route '<1>' (port: '44300', hostname: 'null') from application '<2>' (name: '<route 1 name>', space: '<3>')
[...]
[Controller.Route]-[log]-[1584939]-[map-route (8688) - 1408532]: Mapped route '<1>' (port: '44300', hostname: 'null') to application '<2>' (name: '<route 1 name>', space: '<3>')
[...]
IcrIAddSingleSystem: Added backend system: SID=0GN, NAME=0GN, SRCURL=/, SRCVHOST=<route1 name FQDN>:30033, EXTSRV=http://127.0.0.1:50946#<...>, SSL_IGNORE_HOST_MISMATCH=true
[...]

SAP HANA Extended Application Services, Advanced Model

platform router, web dispatcher, sap web dispatcher, wdp, sap wdp, external web dispatcher, external, routing, xsa routing , KBA , BC-XS-RT , XS Advanced Runtime / XS Controller , BC-CST-WDP , Web Dispatcher , Problem