Error:

1 exception(s):
Exception #0 (SodiumException): This is not implemented, as it is not possible to implement Argon2i with acceptable performance in pure-PHP

Exception #0 (SodiumException): This is not implemented, as it is not possible to implement Argon2i with acceptable performance in pure-PHP
<pre>#1 sodium_crypto_pwhash() called at [vendor/magento/framework/Encryption/Encryptor.php:594]
#2 Magento\Framework\Encryption\Encryptor->getArgonHash() called at [vendor/magento/framework/Encryption/Encryptor.php:225]
#3 Magento\Framework\Encryption\Encryptor->getHash() called at [vendor/magento/module-user/Model/User.php:731]
#4 Magento\User\Model\User->_getEncodedPassword() called at [vendor/magento/module-user/Model/User.php:293]
#5 Magento\User\Model\User->beforeSave() called at [generated/code/Magento/User/Model/User/Interceptor.php:23]
#6 Magento\User\Model\User\Interceptor->beforeSave() called at [vendor/magento/framework/Model/ResourceModel/Db/AbstractDb.php:412]
#7 Magento\Framework\Model\ResourceModel\Db\AbstractDb->save() called at [vendor/magento/framework/Model/AbstractModel.php:655]
#8 Magento\Framework\Model\AbstractModel->save() called at [vendor/magento/framework/Interception/Interceptor.php:58]
#9 Magento\User\Model\User\Interceptor->___callParent() called at [vendor/magento/framework/Interception/Interceptor.php:138]
#10 Magento\User\Model\User\Interceptor->Magento\Framework\Interception\{closure}() called at [vendor/magento/framework/Interception/Interceptor.php:153]
#11 Magento\User\Model\User\Interceptor->___callPlugins() called at [generated/code/Magento/User/Model/User/Interceptor.php:581]
#12 Magento\User\Model\User\Interceptor->save() called at [vendor/magento/module-user/Observer/Backend/AuthObserver.php:149]
#13 Magento\User\Observer\Backend\AuthObserver->execute() called at [vendor/magento/framework/Event/Invoker/InvokerDefault.php:88]
#14 Magento\Framework\Event\Invoker\InvokerDefault->_callObserverMethod() called at [vendor/magento/framework/Event/Invoker/InvokerDefault.php:74]
#15 Magento\Framework\Event\Invoker\InvokerDefault->dispatch() called at [vendor/magento/framework/Event/Manager.php:66]
#16 Magento\Framework\Event\Manager->dispatch() called at [generated/code/Magento/Framework/Event/Manager/Proxy.php:95]
#17 Magento\Framework\Event\Manager\Proxy->dispatch() called at [vendor/magento/module-user/Model/User.php:603]
#18 Magento\User\Model\User->authenticate() called at [generated/code/Magento/User/Model/User/Interceptor.php:140]
#19 Magento\User\Model\User\Interceptor->authenticate() called at [vendor/magento/module-user/Model/User.php:653]
#20 Magento\User\Model\User->login() called at [generated/code/Magento/User/Model/User/Interceptor.php:158]
#21 Magento\User\Model\User\Interceptor->login() called at [vendor/magento/module-backend/Model/Auth.php:162]
#22 Magento\Backend\Model\Auth->login() called at [vendor/magento/framework/Interception/Interceptor.php:58]
#23 Magento\Backend\Model\Auth\Interceptor->___callParent() called at [vendor/magento/framework/Interception/Interceptor.php:138]
#24 Magento\Backend\Model\Auth\Interceptor->Magento\Framework\Interception\{closure}() called at [vendor/magento/framework/Interception/Interceptor.php:153]
#25 Magento\Backend\Model\Auth\Interceptor->___callPlugins() called at [generated/code/Magento/Backend/Model/Auth/Interceptor.php:59]
#26 Magento\Backend\Model\Auth\Interceptor->login() called at [vendor/magento/module-backend/App/Action/Plugin/Authentication.php:205]
#27 Magento\Backend\App\Action\Plugin\Authentication->_performLogin() called at [vendor/magento/module-backend/App/Action/Plugin/Authentication.php:157]
#28 Magento\Backend\App\Action\Plugin\Authentication->_processNotLoggedInUser() called at [vendor/magento/module-backend/App/Action/Plugin/Authentication.php:125]
#29 Magento\Backend\App\Action\Plugin\Authentication->aroundDispatch() called at [vendor/magento/framework/Interception/Interceptor.php:135]
#30 Magento\Backend\Controller\Adminhtml\Index\Index\Interceptor->Magento\Framework\Interception\{closure}() called at [vendor/magento/framework/Interception/Interceptor.php:153]
#31 Magento\Backend\Controller\Adminhtml\Index\Index\Interceptor->___callPlugins() called at [generated/code/Magento/Backend/Controller/Adminhtml/Index/Index/Interceptor.php:32]
#32 Magento\Backend\Controller\Adminhtml\Index\Index\Interceptor->dispatch() called at [vendor/magento/framework/App/FrontController.php:186]
#33 Magento\Framework\App\FrontController->processRequest() called at [vendor/magento/framework/App/FrontController.php:118]
#34 Magento\Framework\App\FrontController->dispatch() called at [vendor/magento/framework/Interception/Interceptor.php:58]
#35 Magento\Framework\App\FrontController\Interceptor->___callParent() called at [vendor/magento/framework/Interception/Interceptor.php:138]
#36 Magento\Framework\App\FrontController\Interceptor->Magento\Framework\Interception\{closure}() called at [vendor/magento/framework/Interception/Interceptor.php:153]
#37 Magento\Framework\App\FrontController\Interceptor->___callPlugins() called at [generated/code/Magento/Framework/App/FrontController/Interceptor.php:23]
#38 Magento\Framework\App\FrontController\Interceptor->dispatch() called at [vendor/magento/framework/App/Http.php:116]
#39 Magento\Framework\App\Http->launch() called at [generated/code/Magento/Framework/App/Http/Interceptor.php:23]
#40 Magento\Framework\App\Http\Interceptor->launch() called at [vendor/magento/framework/App/Bootstrap.php:263]
#41 Magento\Framework\App\Bootstrap->run() called at [pub/index.php:29]
</pre>

Solution:

In the Terminal, type below commands:

cd /usr/src/
wget https://download.libsodium.org/libsodium/releases/libsodium-1.0.18.tar.gz
tar -zxvf libsodium-1.0.18.tar.gz 
cd libsodium*

./configure
make && make check
make install
make check

/opt/cpanel/ea-php74/root/usr/bin/pecl install libsodium

/bin/systemctl restart httpd.service

Now check the Admin Url. It will login successfully !!

Happy Learning !!

Thank you !!