VB6 application for Whatsapp management -- 2

Job ID: 33373509

Budget: €30 – €250 EUR

I'd to make small software to allow users to sends and receives WhatsApp messages inside our current VB6 application.
VB6 source code of current application cannot be shared.
No C#, no Java, no third party controls, no compiled objects.

Deliver this project should be with source code only... to enable us to implement the source-code inside our software.
Final EXE or DLL project is not important (but via source code).
In case of DLL, a .Net compliance must be guarantee.

The final user is a company that manage BUS.
To do it, he use a VB6 application done by me 10 yrs ago (Damages, allocations, customers, ...)
Now, he wants to add a WhatsApp functionallity (inside the actual application, not outside) to call the bus-drivers, send messages, maps pictures, .... and receive by the bus-drivers feedbacks, news, new opportunuty, ....

For example:
* to driver1= give us your position
* to driver2= send a picture of damage
* to driver3= write your driver licence code
....
See the attached schema.

No new graphical interface needed. This means that I ask for VB6 source code, not compiled.
Points of attention: bus-driver are more than 2, this means that new VB6 function has to manage 3 (or more) whatsApp number/account in the same application (problems with login/auth process WITHOUT using QR CODE and INSTANCE_ID, CLIENT_ID, CLIENT_SECRET)

No urgency. Start as soon as possible - daily update is requested, to avoid time loss and misunderstandings about requirements.
No upfront. No payment before successful completion of all tests. Source-code required for test.
Bonuses are provided at the end of the project for compliance with the timing and quality of the software.