Poor response

PNR R3CDY1 this is my booking reference. I bought my ticket online and paid it via eft on the 19th of September 2021. Just after 4am the morning of the 20th I received an email that my payment isn't made. During the day on the 20th of September 2021 I contacted safair and a voice recording said they would phone me back due to high call volumes and I had to leave my cell number. By the evening of the 20th of Sept 2021 I had still not received a call back. I then sent an email and the response on the email was that someone will get back to me. Well its the 21st September 2021 and it's 13h11 and still no call or email from safair. I feel they are very unprofessional with regards to customer service. I encounter the same problem a few month ago when I flew my niece to East London only to get to the airport and be told that payment hasn't been made. I therefore had to forward proof before letting her board and she almost missed her flight