Firebase database authentication issue

[Tosin]

I have an issue and I need help, this issue has shut down my application full functionality for weeks, below is the error...

Unauthorized request. {"userId":5,"exception":"[object] (Kreait\\Firebase\\Exception\\Database\\UnsupportedQuery(code: 401): Unauthorized request. at /var/www/zap-baloe/vendor/kreait/firebase-php/src/Firebase/Database/Query.php:92)

[stacktrace]
#0 /var/www/zap-baloe/vendor/kreait/firebase-php/src/Firebase/Database/Query.php(115): Kreait\\Firebase\\Database\\Query->getSnapshot()
#1 /var/www/zap-baloe/app/Http/Controllers/Api/V1/Request/DeliveryCreateRequestController.php(314): Kreait\\Firebase\\Database\\Query->getValue()

[Jesse Jones]

Googled: "Firebase code: 401)

Result: If you receive a 401 HTTP status code, your Server key is not valid.