Hey @GokulNandan - What's the exact model of your Oppo device? Are you able to use the device with another network at all?
Thanks for the update, @GokulNandan. What network are you currently using?
I’m having the exact same issue with a ZTE.. Paid the $25 to have it unlocked, enter the PIN number I was given with my receipt number after purchase and it looked like it was successful.. Put my Telstra Sim in and it won’t let me make or receive calls, I can send and receive text messages and browse the web, but no phone calls.. I have been researching for over 4 HOURS and have tried every trouble shooting step known to man and still nothing.. EXTREMELY FRUSTRATING!!!!
You talk to Optus and they tell you it must be a phone or Telstra issue but it is not!!! The phones work, and the other carriers’ SIM cards work perfectly in any other unlocked phone.. I have read dozens of forums with A LOT of other people having the EXACT same issue -
Go through the correct process of having an OPTUS phone unlocked, put another carriers SIM card in, can’t make or receive phone calls but can text and browse -
We can’t all be going crazy!!!!!
PLEASE PLEASE PLEASE HELP US OPTUS!! THIS IS A BIG PROBLEM WITHOUT ANY REAL SOLUTIONSS!!!!
Hi @Acid_Princess, prepaid devices that we sell can only support certain frequencies on the 3G network, and as Telstra uses different frequencies, this may impact your ability to make and receive calls. In this instance it may well be that the phone doesn't support the corresponding network.
There is a app that made my phone work. The frequency does not work as the comment below said!!! Yay Optus why is this not told to your customers???
Ok I will send u all info just 2 mins
The app is called mtk engineer app it’s free to download.
Click on android testing
Select phone testing
Change select preferred network to gsm/wcdma (auto)
Click on the options menu, the 3 dots on the top of the corner of your screen
select radio band, first or too option. This should bring up the set the gsm/utms band mode menu
This will unlock your frequency but you have to do this each time u turn your phone of or restarts.
I got this info on here. Hope this helps guys!
Hi, I was with optus, I bought a new sim from belong which runs on telstra network. I have tried to fix this issue by downloading the mkt engineer app but you can't alter settings on an oppo A73 models. I guess I'll just have to write a formal complaint and let the people higher up know about this major issue which packs some really misleading infor, thanks to optus
Thank you for replying @Tano, but that doesn’t help anyone here at all.. I think it beggars belief that you just told me that OPTUS is aware that there can be a “frequency glitch” with phones locked to OPTUS being unlocked and used with another carriers SIM card..
But isn’t the point of PAYING to UNLOCK an Optus phone, is that it should be unlocked to freely use other carriers SIM cards?!?!?!?!?!
Where is the consumers warning that it MAY STILL NOT WORK once unlocked to anyone but Optus ANYWAY?!?!?!
Where was the disclaimer before charging customers for the unlock fee?!?!?!?
If I had known it might not work anyway after PAYING, I would not have gone through with it, I would have just bought a new unlocked phone.. I agree entirely with @GokulNandan, I will be writing a formal complaint to Optus because that is really not good enough, and I’m sure there is something not quite legal with this at all...
Had the same problem with my oppo a73 when I unlocked it and tried to use the Belong (Telstra) network.
Searched everywhere (and found this page) to no avail.
Then I found out how to change it so I thought I would register an account and post the solution here.
(1) Enter *#800#* to open the MTK engineering settings.
Go to Telephony> Bandmode> SIM1 and enable the 850 band mode by checking the box and pressing SET.
(2) Change Network Selecting from lte/umts —> lte/utms/gsm
(3) Change Bandmode to include Wcdma-clr-850 enabled
Now I can make instant phone calls