diff --git a/package.json b/package.json
index 8544787d40..ff2a62a3dd 100644
--- a/package.json
+++ b/package.json
@@ -118,7 +118,7 @@
     "lint-fix": "eslint --fix --cache ./",
     "build": "babel src/ -d lib/ --copy-files",
     "watch": "babel --watch src/ -d lib/ --copy-files",
-    "test:mongodb:runnerstart": "cross-env mongodb-runner start -t standalone --version $npm_config_dbversion -- --port 27017",
+    "test:mongodb:runnerstart": "cross-env mongodb-runner stop --all && mongodb-runner start -t standalone --version $npm_config_dbversion -- --port 27017",
     "test:mongodb:testonly": "cross-env MONGODB_VERSION=${MONGODB_VERSION:=$npm_config_dbversion} MONGODB_TOPOLOGY=${MONGODB_TOPOLOGY:=standalone} TESTING=1 jasmine",
     "test:mongodb": "npm run test:mongodb:runnerstart --dbversion=$npm_config_dbversion && npm run test:mongodb:testonly --dbversion=$npm_config_dbversion",
     "test:mongodb:4.2.19": "npm run test:mongodb --dbversion=4.2.19",
diff --git a/src/Adapters/Storage/Mongo/MongoStorageAdapter.js b/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
index cdaccbb709..268a9ed1aa 100644
--- a/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
+++ b/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
@@ -31,6 +31,8 @@ const storageAdapterAllCollections = mongoAdapter => {
     .connect()
     .then(() => mongoAdapter.database.collections())
     .then(collections => {
+      if (!collections || !collections.length) return [];
+
       return collections.filter(collection => {
         if (collection.namespace.match(/\.system\./)) {
           return false;
@@ -399,6 +401,7 @@ export class MongoStorageAdapter implements StorageAdapter {
   }
 
   deleteAllClasses(fast: boolean) {
+    // @flow-disable-next
     return storageAdapterAllCollections(this).then(collections =>
       Promise.all(
         collections.map(collection => (fast ? collection.deleteMany({}) : collection.drop()))