'__VLS_ctx.balance' is possibly 'undefined'.

Property 'next' does not exist on type '{ $: ComponentInternalInstance; $data: {}; $props: Partial<{}> & Omit<{} & VNodeProps & AllowedComponentProps & ComponentCustomProps & Readonly<...>, never>; ... 10 more ...; $watch<T extends string | ((...args: any) => any)>(source: T, cb: T extends (...args: any) => infer R ? (args_0: R, args_1: R) => any : (...ar...'.