My Oppo 474 LCD has purple spots and they increase in number every day

@kangdan your phone has a broken display. The only way of fixing it, is by replacing it. Since iFixit doesn't yet have a specific guide for this, use something like this video Replacement screens are available at many onlines stores.

While you work on your phone, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has a device with the same issues as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!