Phone not linked to app PROBLEM. Frustrating as it I unlinked and relinked but still not working

Payment via ozow not processed due to "cellphone not linked". I unlinked all phones on app and logged in again and linked 2 phones. Did digime successfully. EAP etc checked but still same message. Called customer service after 10 mins I explained problem. Sat on phone for another 10 mins and call was cut off. NO CALLBACK received. How can their Payment system be so unstable? Why do I have to do digime every few months? I'm on the phone again to customer service.... waiting 7 mins. PATHETIC SYSTEM. Got through and had yo explain everything again. Will be escalated to backoffice. The more they try to make it simple, the more difficult it gets to Transact!