My site is working fine but existing customer can’t login. Is ther any way to resolve this isssue??
Magento 1 used MD5 Algorithm to store customer passwords whereas in Magento 2, SHA256 Algorithm is made use. So try running this command to upgrade customer' s hash according to the latest algorithm
php bin/magento customer:hash:upgrade
You need to manually upgrade your password_hash using md5 to sha256, Once you are done with migration, run below command:
php -f bin/magento customer:hash:upgrade