this mobile device is not a locked optus prepaid mobile device. OPPO A73

[OPPOA73Help]

I am getting this mobile device is not a locked optus prepaid mobile device. message when I use my IMEI to unlock my mobile

How do I get unlock code please advice appreciate your help

IMEI 866461037277164

[pwright]

You may have to ring the Prepaid Care Team on 1300555002 and request it over the phone, as its a new device and the codes may not be loaded in the Optus Website yet.  Just be mindful this device has 3G 850 support removed, so its not much use on the Telstra Network even when unlocked (for voice calls anyway). It will work on Vodafone as Vodafone have 3G 900, same as Optus, but unless you are un 3G 2100 zones on Telstra, you wont be able to make a call on this handset. 

[paulcl]

Not sure what all of that jargon means but my wife has this phone and uses Aldi Mobile (Telstra) with no problems.  

[pwright]

Was the phone sold through Optus?, Oppo's directly sold version supports 3G 850?  Optus's verson has 3G 850, which is the Core of Telstra's 3G network removed out of the device, meaning it will only connect for Voice Calls on 3G (Does not support VOLTE, calls over 4G) on 900/2100 3G.  Your wife may be in a Telstra 2100 3G zone, but if she goes outside a CBD area, she may fall back to 3G 850 on Aldi/Telstra Mobile and not be able to make a call, as it would only have Internet Access over LTE and not make a call with no 3G 850 support if outside a 2100 3G zone on Telstra.