我也遇到了同样的情况，在使用分包的情况下，跳转分包下的页面时，无法跳转，走了系统onPageNotFound的回调，

这是实时日志的打印内容，

[10:02:21]  App onPageNotFound {"path":"packagesHome/pages/index/index","rawPath":"packagesHome/pages/index/index.html","qualityData":{"isWebviewPreload":true,"navId":"-1139044571_1602640940170","isPreloadPageFrame":true},"preloadRule":null,"query":{},"resizing":false,"notFound":true,"page":{"window":{"navigationBarBackgroundColor":"#ffff","usingComponents":{"header-view":"../../components/header-view/index","header-title":"../../components/header-title/index","week-plan":"../../components/week-plan/index","banner-view":"../../components/banner-view/index","weather":"../../components/weather/index","purchase-order":"../../components/purchase-order/index","goods-statistics":"../../components/goods-statistics/index","recommend-goods":"../../components/recommend-goods/index","history-order":"../../components/history-order/index","van-icon":"/miniprogram/miniprogram_npm/@vant/weapp/icon/index","van-row":"/miniprogram/miniprogram_npm/@vant/weapp/row/index","van-col":"/miniprogram/miniprogram_npm/@vant/weapp/col/index","van-overlay":"/miniprogram/miniprogram_npm/@vant/weapp/overlay/index","custom-page":"/components/custom-page/index","van-popup":"/miniprogram/miniprogram_npm/@vant/weapp/popup/index"}}},"prerender":false,"openType":"navigateTo"}

以下是做的分包设置，

明明在分包中有对应的页面，但是还是会出现onPageNotFound的回调，无法正确跳转，因为还未发布过正式版，这样的情况只在体验版中出现过，而且还是偶发性的，删除重新加载小程序的时候，有的时候就会正常跳转了，

麻烦提供能复现问题的简单代码片段（https://developers.weixin.qq.com/miniprogram/dev/devtools/minicode.html）。