[BUG][WEBJS] `TypeError: Cannot read properties of undefined (reading 'getContact'/'getChat')` on `/api/contacts` and `/api/sendText`
Author: jesaiasmaiaCreated Mar 4, 2026Updated Sep 16, 2026
Labelsbugengine:WEBJS
Describe the bug
On WAHA 2026.2.2 (WEBJS, PLUS), requests to GET /api/contacts and POST /api/sendText are intermittently failing with HTTP 500.
The internal stack trace points to whatsapp-web.js evaluate context:
WebjsClientPlus.getContactById->reading 'getContact'WebjsClientPlus.sendMessage->reading 'getChat'
This happens even for simple text messages and valid @c.us numbers.
WAHA version
{
"version": "2026.2.2",
"engine": "WEBJS",
"tier": "PLUS",
"browser": "/usr/bin/chromium",
"platform": "linux/x64"
}
Request samples
Failing contacts lookup
GET /api/contacts?contactId=5511999640873@c.us&session=<session_name>
Response:
{
"statusCode": 500,
"exception": {
"message": "Cannot read properties of undefined (reading 'getContact')",
"stack": "TypeError: Cannot read properties of undefined (reading 'getContact') ... at WebjsClientPlus.getContactById ..."
}
}
Failing text send
POST /api/sendText
Response/log:
{
"statusCode": 500,
"err": {
"message": "Cannot read properties of undefined (reading 'getChat')",
"stack": "TypeError: Cannot read properties of undefined (reading 'getChat') ... at WebjsClientPlus.sendMessage ..."
}
}
Steps to reproduce
Create/start a WEBJS session in WAHA PLUS.
Confirm session is WORKING.
Call:
GET /api/contacts?contactId=<phone>@c.us&session=<session>
Or call:
POST /api/sendText with valid session, chatId, and plain text.
Observe intermittent HTTP 500 with getContact or getChat undefined.
Expected behavior
/api/contacts should return contact data or a domain error (not runtime TypeError).
/api/sendText should send plain text successfully.
Actual behavior
Runtime TypeError inside WEBJS evaluate context (undefined.getContact / undefined.getChat), returning HTTP 500.
Additional context
Restart/logout of session may temporarily help, but issue can reappear.
Looks like internal WEBJS state/context inconsistency.Source: devlikeapro/waha