My app got rejected due to
Guideline 3.2 - Business
We found that your app is not appropriate for the App Store since it is designed specifically for AppName.
It would be more appropriate to distribute and sell your app as a custom B2B app, directly to your business customers, through the Volume Purchase Program. You can find additional information regarding the Volume Purchase Program and the Custom B2B App Store in iTunes Connect Developer Help.
Now I also join the Volume Purchase Program with another apple id but now I don't now what to do next, How I can distribute my app ?
AppStore is a public portal that is meant for all the people. If your App is to be on the AppStore, then a wide majority of people should be able to use your application.
If your app is only for a specific company, then it wont fit to be in the AppStore since many people will see it, download it, find it useless and delete it (since they have no access to anything, it's a waste of time for them).
I had 3 clients who wanted apps specific for their company. I send them the app OTA (Over the Air)
My suggestion is to let the company employees install the app OTA (Over the air) where you send them a link to download the app and it downloads itself on their device. This also provides better security since only the people eligible to download the app would have the download link.
After all you don't want people downloading the app, finding it useless and down voting it since it was a waste of time for them
Hope it helps!