OPPO A16s

I am very dissapointed in the Oppo mobile phones. I have been trying to get a callback on collecting my phone to have the screen replaced. Cannot find a screen at any cellphone shops. They promise they will call back but with no luck. I have all the sms messages from them to say thank you for calling oppo. Please rate our service. I gave them a bad review then 1 person called me not to call back. Hope they will respond