I can't download apps from Play Store

[AC Question]

I'm using the device Doogee x5 pro and I can't download apps. Every time I get an error retrieving information from server: [RPC:S-7:AEC-0 DR5J-63P5-FJEB2].I have tried to fix it but nothing. I have seen Google guides to fix it but I still need help.

 

[AlphaTango414]

Wipe app data via application manager. Wipe system cache via recovery. That's where I would start first.

 

[helpas]

This might sound silly but.. where do I find it?