With Guardarian Pro, clients can check their transaction history and transaction details of past orders and initiate new transactions as well! The login process consists of simple authentication (email or SMS), which should already be familiar to existing clients. Just make sure to use the same email/Phone nr which was used to initiate your previous transactions.
Please note that Guardarian is still an account-free service, which does not require a login step for placing orders. You can still perform transactions without using Guardarian Pro.