useContext on TypeScript, how?😢😥

Question

https://www.sololearn.com/compiler-playground/ctO3yvHpfvyj

My problem is, I can't call the properties of my created context. Please be soft to correct me since I already know that I'm having a hard time in useContext hooks and using types/interface of TypeScript.

Please check this code
https://www.sololearn.com/compiler-playground/ctO3yvHpfvyj

EDIT: This is working on latest version of TypeScript; it's just I'm putting my code into SPFx of Microsoft which uses old version of Typescript.

//---------------THE ERROR--------------------
[08:04:51] Error - [tsc] src/webparts/onlineShop/components/header/ShopHeader/HeaderImage.tsx(12,21): error TS2339: Property 'timer' does not exist on type 'unknown'.
[08:04:51] Error - [tsc] src/webparts/onlineShop/components/header/ShopHeader/HeaderImage.tsx(23,60): error TS2339: Property 'images' does not exist on type 'unknown'.