diff --git a/package-lock.json b/package-lock.json
index a9085de..2250942 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -419,6 +419,23 @@
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@@ -724,7 +755,6 @@
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@@ -736,9 +766,9 @@
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+      "resolved": "https://registry.npmjs.org/@openzeppelin/contracts/-/contracts-4.4.2.tgz",
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@@ -1266,7 +1327,6 @@
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@@ -1586,6 +1646,59 @@
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+            "xhr": "^2.2.0",
+            "xtend": "^4.0.1"
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+                "create-hash": "^1.1.2",
+                "elliptic": "^6.5.2",
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+          "resolved": "https://registry.npmjs.org/ws/-/ws-5.2.3.tgz",
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@@ -2084,7 +2226,6 @@
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@@ -2190,6 +2331,15 @@
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@@ -2205,6 +2355,15 @@
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@@ -3337,6 +3496,12 @@
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@@ -5420,6 +5585,32 @@
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@@ -9559,6 +9832,12 @@
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-      "requires": {
-        "scryptsy": "^2.1.0",
-        "semver": "^6.3.0"
-      },
-      "dependencies": {
-        "semver": {
-          "version": "6.3.0",
-          "resolved": "https://registry.npmjs.org/semver/-/semver-6.3.0.tgz",
-          "integrity": "sha512-b39TBaTSfV6yBrapU89p5fKekE2m/NwnDocOVruQFS1/veMgdzuPcnOM34M6CwxW8jH/lxEa5rBoDeUwu5HHTw==",
-          "dev": true
-        }
-      }
-    },
     "scrypt.js": {
       "version": "0.3.0",
       "resolved": "https://registry.npmjs.org/scrypt.js/-/scrypt.js-0.3.0.tgz",
@@ -18616,81 +18878,6 @@
         "web3-utils": "1.2.1"
       }
     },
-    "web3-provider-engine": {
-      "version": "git+https://github.com/trufflesuite/provider-engine.git#3538c60bc4836b73ccae1ac3f64c8fed8ef19c1a",
-      "from": "git+https://github.com/trufflesuite/provider-engine.git#web3-one",
-      "dev": true,
-      "requires": {
-        "async": "^2.5.0",
-        "backoff": "^2.5.0",
-        "clone": "^2.0.0",
-        "cross-fetch": "^2.1.0",
-        "eth-block-tracker": "^3.0.0",
-        "eth-json-rpc-infura": "^3.1.0",
-        "eth-sig-util": "^1.4.2",
-        "ethereumjs-block": "^1.2.2",
-        "ethereumjs-tx": "^1.2.0",
-        "ethereumjs-util": "^5.1.5",
-        "ethereumjs-vm": "^2.3.4",
-        "json-rpc-error": "^2.0.0",
-        "json-stable-stringify": "^1.0.1",
-        "promise-to-callback": "^1.0.0",
-        "readable-stream": "^2.2.9",
-        "request": "^2.85.0",
-        "semaphore": "^1.0.3",
-        "ws": "^5.1.1",
-        "xhr": "^2.2.0",
-        "xtend": "^4.0.1"
-      },
-      "dependencies": {
-        "ethereumjs-tx": {
-          "version": "1.3.7",
-          "resolved": "https://registry.npmjs.org/ethereumjs-tx/-/ethereumjs-tx-1.3.7.tgz",
-          "integrity": "sha512-wvLMxzt1RPhAQ9Yi3/HKZTn0FZYpnsmQdbKYfUUpi4j1SEIcbkd9tndVjcPrufY3V7j2IebOpC00Zp2P/Ay2kA==",
-          "dev": true,
-          "requires": {
-            "ethereum-common": "^0.0.18",
-            "ethereumjs-util": "^5.0.0"
-          }
-        },
-        "ethereumjs-util": {
-          "version": "5.2.0",
-          "resolved": "https://registry.npmjs.org/ethereumjs-util/-/ethereumjs-util-5.2.0.tgz",
-          "integrity": "sha512-CJAKdI0wgMbQFLlLRtZKGcy/L6pzVRgelIZqRqNbuVFM3K9VEnyfbcvz0ncWMRNCe4kaHWjwRYQcYMucmwsnWA==",
-          "dev": true,
-          "requires": {
-            "bn.js": "^4.11.0",
-            "create-hash": "^1.1.2",
-            "ethjs-util": "^0.1.3",
-            "keccak": "^1.0.2",
-            "rlp": "^2.0.0",
-            "safe-buffer": "^5.1.1",
-            "secp256k1": "^3.0.1"
-          }
-        },
-        "keccak": {
-          "version": "1.4.0",
-          "resolved": "https://registry.npmjs.org/keccak/-/keccak-1.4.0.tgz",
-          "integrity": "sha512-eZVaCpblK5formjPjeTBik7TAg+pqnDrMHIffSvi9Lh7PQgM1+hSzakUeZFCk9DVVG0dacZJuaz2ntwlzZUIBw==",
-          "dev": true,
-          "requires": {
-            "bindings": "^1.2.1",
-            "inherits": "^2.0.3",
-            "nan": "^2.2.1",
-            "safe-buffer": "^5.1.0"
-          }
-        },
-        "ws": {
-          "version": "5.2.2",
-          "resolved": "https://registry.npmjs.org/ws/-/ws-5.2.2.tgz",
-          "integrity": "sha512-jaHFD6PFv6UgoIVda6qZllptQsMlDEJkTQcybzzXDYM1XO9Y8em691FGMPmM46WGyLU4z9KMgQN+qrux/nhlHA==",
-          "dev": true,
-          "requires": {
-            "async-limiter": "~1.0.0"
-          }
-        }
-      }
-    },
     "web3-providers-http": {
       "version": "1.2.1",
       "resolved": "https://registry.npmjs.org/web3-providers-http/-/web3-providers-http-1.2.1.tgz",
@@ -18722,7 +18909,7 @@
       "dependencies": {
         "websocket": {
           "version": "github:web3-js/WebSocket-Node#905deb4812572b344f5801f8c9ce8bb02799d82e",
-          "from": "github:web3-js/WebSocket-Node#polyfill/globalThis",
+          "from": "github:web3-js/WebSocket-Node#905deb4812572b344f5801f8c9ce8bb02799d82e",
           "requires": {
             "debug": "^2.2.0",
             "es5-ext": "^0.10.50",
diff --git a/package.json b/package.json
index e46712b..ac9361d 100644
--- a/package.json
+++ b/package.json
@@ -11,7 +11,7 @@
   },
   "license": "MIT",
   "dependencies": {
-    "@openzeppelin/contracts": "2.4.0",
+    "@openzeppelin/contracts": "4.4.2",
     "@openzeppelin/contracts-ethereum-package": "^2.4.0",
     "dotenv": "^8.2.0",
     "truffle-hdwallet-provider": "^1.0.17"