diff --git a/package-lock.json b/package-lock.json
index 74517c5..85d1c6e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -186,11 +186,6 @@
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@@ -347,9 +342,9 @@
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@@ -519,9 +514,9 @@
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@@ -946,11 +941,6 @@
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@@ -1274,33 +1264,36 @@
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-      "integrity": "sha512-g+ShTQYLsCcOUkNOK6CCEZbj3aRDVPw3WOwXk+LxlUKvuS9ujEqP2MppBHyRVYrNNFW/vcPaTBUZ2ctGNSiOCA==",
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-        "cluster-key-slot": "1.0.8",
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-        "denque": "1.2.3",
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+      "resolved": "https://registry.npmjs.org/ioredis/-/ioredis-4.27.8.tgz",
+      "integrity": "sha512-AcMEevap2wKxNcYEybZ/Qp+MR2HbNNUwGjG4sVCC3cAJ/zR9HXKAkolXOuR6YcOGPf7DHx9mWb/JKtAGujyPow==",
+      "requires": {
+        "cluster-key-slot": "^1.1.0",
+        "debug": "^4.3.1",
+        "denque": "^1.1.0",
+        "lodash.defaults": "^4.2.0",
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+        "lodash.isarguments": "^3.1.0",
+        "p-map": "^2.1.0",
+        "redis-commands": "1.7.0",
+        "redis-errors": "^1.2.0",
+        "redis-parser": "^3.0.0",
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+          "resolved": "https://registry.npmjs.org/debug/-/debug-4.3.2.tgz",
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+        }
       }
     },
     "ipaddr.js": {
@@ -1489,91 +1482,26 @@
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-      "resolved": "https://registry.npmjs.org/lodash.bind/-/lodash.bind-4.2.1.tgz",
-      "integrity": "sha1-euMBfpOWIqwxt9fX3LGzTbFpDTU="
-    },
-    "lodash.clone": {
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-      "resolved": "https://registry.npmjs.org/lodash.clone/-/lodash.clone-4.5.0.tgz",
-      "integrity": "sha1-GVhwRQ9aExkkeN9Lw9I9LeoZB7Y="
-    },
-    "lodash.clonedeep": {
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-      "resolved": "https://registry.npmjs.org/lodash.clonedeep/-/lodash.clonedeep-4.5.0.tgz",
-      "integrity": "sha1-4j8/nE+Pvd6HJSnBBxhXoIblzO8="
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-      "resolved": "https://registry.npmjs.org/lodash.difference/-/lodash.difference-4.5.0.tgz",
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-      "resolved": "https://registry.npmjs.org/lodash.noop/-/lodash.noop-3.0.1.tgz",
-      "integrity": "sha1-OBiPTWUKOkdCWEObluxFsyYXEzw="
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-      "integrity": "sha1-SfPYz9qjv/izqR0SfpIyRUGJYdQ="
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-    "lodash.pick": {
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-      "resolved": "https://registry.npmjs.org/lodash.pick/-/lodash.pick-4.4.0.tgz",
-      "integrity": "sha1-UvBWEP/53tQiYRRB7R/BI6AwAbM="
+    "lodash.isarguments": {
+      "version": "3.1.0",
+      "resolved": "https://registry.npmjs.org/lodash.isarguments/-/lodash.isarguments-3.1.0.tgz",
+      "integrity": "sha1-L1c9hcaiQon/AGY7SRwdM4/zRYo="
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-      "integrity": "sha1-XkKRsMdT+hq+sKq4+ynfG2bwf20="
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-    "lodash.shuffle": {
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-      "resolved": "https://registry.npmjs.org/lodash.shuffle/-/lodash.shuffle-4.2.0.tgz",
-      "integrity": "sha1-FFtQU8+HX29cKjP0i26ZSMbse0s="
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-    "lodash.values": {
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-      "resolved": "https://registry.npmjs.org/lodash.values/-/lodash.values-4.3.0.tgz",
-      "integrity": "sha1-o6bCsOvsxcLLocF+bmIP6BtT00c="
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@@ -1793,6 +1721,11 @@
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+    "p-map": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/p-map/-/p-map-2.1.0.tgz",
+      "integrity": "sha512-y3b8Kpd8OAN444hxfBbFfj1FY/RjtTd8tzYwhUqNYXx0fXx2iX4maP4Qr6qhIKbQXI02wTLAda4fYUbDagTUFw=="
+    },
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@@ -2016,14 +1949,22 @@
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-      "resolved": "https://registry.npmjs.org/redis-commands/-/redis-commands-1.3.5.tgz",
-      "integrity": "sha512-foGF8u6MXGFF++1TZVC6icGXuMYPftKXt1FBT2vrfU9ZATNtZJ8duRC5d1lEfE8hyVe3jhelHGB91oB7I6qLsA=="
+      "version": "1.7.0",
+      "resolved": "https://registry.npmjs.org/redis-commands/-/redis-commands-1.7.0.tgz",
+      "integrity": "sha512-nJWqw3bTFy21hX/CPKHth6sfhZbdiHP6bTawSgQBlKOVRG7EZkfHbbHwQJnrE4vsQf0CMNE+3gJ4Fmm16vdVlQ=="
+    },
+    "redis-errors": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/redis-errors/-/redis-errors-1.2.0.tgz",
+      "integrity": "sha1-62LSrbFeTq9GEMBK/hUpOEJQq60="
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-      "version": "2.6.0",
-      "resolved": "https://registry.npmjs.org/redis-parser/-/redis-parser-2.6.0.tgz",
-      "integrity": "sha1-Uu0J2srBCPGmMcB+m2mUHnoZUEs="
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/redis-parser/-/redis-parser-3.0.0.tgz",
+      "integrity": "sha1-tm2CjNyv5rS4pCin3vTGvKwxyLQ=",
+      "requires": {
+        "redis-errors": "^1.0.0"
+      }
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     "referrer-policy": {
       "version": "1.1.0",
@@ -2285,6 +2226,11 @@
         "tweetnacl": "0.14.5"
       }
     },
+    "standard-as-callback": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/standard-as-callback/-/standard-as-callback-2.1.0.tgz",
+      "integrity": "sha512-qoRRSyROncaz1z0mvYqIE4lCd9p2R90i6GxW3uZv5ucSu8tU7B5HXUP1gG8pVZsYNVaXjk8ClXHPttLyxAL48A=="
+    },
     "statuses": {
       "version": "1.4.0",
       "resolved": "https://registry.npmjs.org/statuses/-/statuses-1.4.0.tgz",
diff --git a/package.json b/package.json
index 1846516..304d376 100644
--- a/package.json
+++ b/package.json
@@ -23,7 +23,7 @@
     "express": "^4.16.3",
     "g": "^2.0.1",
     "helmet": "^3.12.0",
-    "ioredis": "^3.2.2",
+    "ioredis": "^4.27.8",
     "request": "^2.85.0",
     "urlencode": "^1.1.0",
     "yargs": "^11.0.0"