After some testing, I have some doubts about how invoices are generated.

Issue 1
The main problem is that invoices are auto generated for all/any 'financial' operations done by the payment plugin.
This also includes promotional topups as periodical credit to registered users, credit for registration and credit for referral users.

Those operations are virtual credit not a real financial operations nor real incoms. From acountancy point of view those invoices are very incorrect and can put the business owner into big problems. I believe this statement is true for all EU based companies.
And for this reason those promotional topups offered by the payment plugin should be EXCLUDED from the automated invoice generation.

Invoices should be generated ONLY for real payments done via the payment gataways.


Issue 2
In all EU countries the invoice is valid only if buyer data as name/surname and the address are printed (or the company name and the VAT nr).
Where now invoices are genereted based on whatever customer registration data. In most cases it is just username (login) and the email address which appear on invoice as the buyer information. This is wrong in all ways.

I think the invoice plugin should add another form to the user menu called i.e. BILLING INFORMATION where users should state their details for invoices.
And then the plugin should use those details and not just username and email address from the account registration form.
Also invoices should be auto generated per user only after user would fill inn information required on BILLING INFORMATION menu.

I understand that Issue2 requires some work but to fix the Issue1 should be relatively easy (adding conditional checks to the code to check if operation comes from free credits?).
@MBthemes - Can you concider to make those changes please?

@pitter
Issue 1 - sent you fix already
Issue 2 - and in 98% field "billing information" would be empty because user would not fill it

Issue 1 - thank you
Issue 2 - yes, but for remaining 2% of users who wants to receive invoices for their purchase, admin dont have to even touch anything because it all will be on user side.

You can request these data from user and update invoice in backoffice

@pitter
Issue 1 - sent you fix already
Issue 2 - and in 98% field "billing information" would be empty because user would not fill it

I agree with piter, Issue 2 is important

Why don't you change it? If people write that it is important for some users, I think that you couldn't ignore this information.
I also need Billing information. Some people sell in one location but their Billing address is in second location. I paid 30Euro and my users can't write NIP (even if user choose business account) number and Billing information. So what for I paid? If you want earn you should interest what people need.
You write some times ago, that we can write to users and get information from them, but if I write mail and write additional information i also can made invoice in other (external) programs, often better than plugin and I don't need Invoice Plugin. Invoice Plugin should help us, but it don't work good.

I bought some plugins for Osclass to see how it work, because there was Invoice Plugin, but I think that I don't change script in my main website. Osclass work worse than my old  script without something like Invoice Plugin.

@azi_111
https://osclasspoint.com/osclass-plugins/payments-and-shopping/invoice-osclass-plugin-i93

Please try to find any information about custom user VAT numbers or NIP.
You may check how many is there different VAT identification numbers in the world:
https://en.wikipedia.org/wiki/VAT_identification_number

... NIP, UID, DIC, CVR, PVN, NIF, ABN, TIN etc. Each with different format, length and rules behind.


You may reuse city area field, that is not used in most of themes.
Just rename label of this field in front, then in functions.php of plugin find function "inv_header_to" and bellow this line:
    $data[] = $user['s_email'];

add:
    $data[] = $user['s_city_area'];
Field will be added to header of invoice.

1.Thank you for your advice. I try it

2. "You may check how many is there different VAT identification numbers in the world:"
Its only letters and numbers, from 5 to 15:)
You dont must check in Osclass all possibilites of VAT identification numbers. It should be field like Name or City. In different countries people will write it according to local regulations.
"You may reuse city area field, that is not used in most of themes." - field something like this
Vat Numbers in Osclass it can be only possibilites not "must have". Some people will want and use it, some people not.
For example: Some people use Google Maps in Osclass but many people not, but who wants it can
It will be good for website which work in national language and national regulations.