Fixed price payment button

[Bob_be]

@sam2

client is doing like he has 2 tyoe of customers who will buy for normal prices another he has given vouchers which is price of 20

If your client is selling vouchers then a gift certificate would be the proper way of handling it. Here is the KB article for gift certificates:
https://kb.sambapos.com/en/4-31-gift-certificates-sales-and-redemption-implementation/

If your client wants to give a free gift certificate (voucher) there is a mention further down this thread of a way to handle that situation:

Gift Certificate Sales & Redemption

Gift Certificate Sales & Redemption This is a working implementation for Selling & Redeeming variable-value Gift Certificates (GCs) that are tracked under their own individual GC Account and 2 “GC Balance” Accounts called “GC Purchases” and “GC Redemptions”. GC Sale: Customer comes in to purchase a Gift Certificate (GC). Enter the value of the GC that the customer wants to purchase into the NUMBERPAD ($10, $20, etc). Select GC Product (open price). Settle the ticket - customer pays for the G…

@sam2 it would be helpful to the members of the forum, as well as yourself, to describe the whole situation from the get-go. You started this post asking for a Fixed price payment button . I spent time working on that for you with a responds “this did not work for me” (it does work, as seen by the animation). Then you jumped to a zero price definition through a department. Posflow suggested using a gift button. Then 5 days after your original post, you describe what the situation is. You are not new to this forum. You have been around a while and even have helped people, which we all appreciate. But you do not take into consideration the value of people’s time. Everybody here wants to help, but they do not want to waste their time coming up with solutions that do not work for you. It is because of this everybody is reluctant to help you.