(node:9956) UnhandledPromiseRejectionWarning: MongoError: ns not found
    at Function.MongoError.create (/opt/rocket.chat-0.68.3/programs/server/npm/node_modules/meteor/npm-mongo/node_modules/mongodb-core/lib/error.js:31:11)
    at /opt/rocket.chat-0.68.3/programs/server/npm/node_modules/meteor/npm-mongo/node_modules/mongodb-core/lib/connection/pool.js:497:72
    at authenticateStragglers (/opt/rocket.chat-0.68.3/programs/server/npm/node_modules/meteor/npm-mongo/node_modules/mongodb-core/lib/connection/pool.js:443:16)
    at Connection.messageHandler (/opt/rocket.chat-0.68.3/programs/server/npm/node_modules/meteor/npm-mongo/node_modules/mongodb-core/lib/connection/pool.js:477:5)
    at Socket.<anonymous> (/opt/rocket.chat-0.68.3/programs/server/npm/node_modules/meteor/npm-mongo/node_modules/mongodb-core/lib/connection/connection.js:333:22)
    at emitOne (events.js:116:13)
    at Socket.emit (events.js:211:7)
    at addChunk (_stream_readable.js:263:12)
    at readableAddChunk (_stream_readable.js:250:11)
    at Socket.Readable.push (_stream_readable.js:208:10)
    at TCP.onread (net.js:597:20)

(node:9956) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:9956) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.