Poor system interface
You need to provide a transaction reference number after payment is made, which you didn't. Reference number is crucial on case further follow up needed. The SMS acknowledgement is not adequate. You need to provide a weblink for people preferring to use desktop computer to make the payment as not everyone prefer using mobile phone for such transactions. The last step prior to payment is not clear. There should be better explanation that user should review the document so that the mext payment step can proceed. Thank you.