Horrible service

I don't even know where to start, payjoy frustrates me so badly ....i paid my installment on the 24th of June whereas the due date was the 3rd of July...however it seems like no one attends to emails as I sent the Proof of payment. Yesterday the 3rd my phone was locked because of no payment allocated or acknowledged...I called today and I was granted access for some hours ...I see on the app the phone will be locked again tomorrow the 5th which means I won't be able to use the phone after paying 9 days early before the due date...I hope I won't be charged any interests for late payment as I paid in time....it's so frustrating...the agents are also not very nice via the phone or WhatsApp line ...no customer service....the service is very poor ...