On call TypeError: Cannot read properties of undefined (reading 'sendMessage')

[avct-net]

Hello,
KMS is a new technology for me.
I installed a kurento-media-server 7.0. on debian 11.
I access the one2one-call interface correctly.
I can register users.
but when I run the first call I get the following error message :

/home/vincent/kurento/tutorials/javascript-node/one2one-call/server.js:411
    caller.sendMessage(message);

TypeError: Cannot read properties of undefined (reading 'sendMessage')
    at call (/home/vincent/kurento/tutorials/javascript-node/one2one-call/server.js:411:12)
    at WebSocket.<anonymous> (/home/vincent/kurento/tutorials/javascript-node/one2one-call/server.js:245:13)
    at WebSocket.emit (node:events:514:28)
    at WebSocket.emit (node:domain:489:12)
    at Receiver.receiverOnMessage (/home/vincent/kurento/tutorials/javascript-node/one2one-call/node_modules/ws/lib/websocket.js:1068:20)
    at Receiver.emit (node:events:514:28)
    at Receiver.emit (node:domain:489:12)
    at Receiver.dataMessage (/home/vincent/kurento/tutorials/javascript-node/one2one-call/node_modules/ws/lib/receiver.js:517:14)
    at Receiver.getData (/home/vincent/kurento/tutorials/javascript-node/one2one-call/node_modules/ws/lib/receiver.js:435:17)
    at Receiver.startLoop (/home/vincent/kurento/tutorials/javascript-node/one2one-call/node_modules/ws/lib/receiver.js:143:22)

[avct-net]

when I throw
npm install

kurento-one2many-call@7.0.1-dev postinstall
cd static && bower install
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4 high severity vulnerabilities
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has different dependencies.
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npm fund
return
kurento-one2many-call@7.0.1-dev
├── https://github.com/sponsors/ljharb
│ └── minimist@1.2.8, qs@6.11.0, side-channel@1.0.4, call-bind@1.0.2, get-intrinsic@1.2.1, has-proto@1.0.1, has- symbols@1.0.3, object-inspect@1.12.3
└── https://github.com/sponsors/feross
└── safe-buffer@5.2.1