Pass calculation to payment field is not working

I have a problem here too:
https://form.jotform.com/220092455937055/prefill/61de825f6a8b6c66ce53f4173637

I am using conditions to make "Package price" which is a "User defined amount" = $150 if the Reviewing package: value is: Fiction Goodreads starting package
And it doesn't work. What is the solution for this?

The amount can only be passed to the payment field from the Form Calculation widget. Add the Form Calculation widget to the form, update your condition to pass 150 to the Form Calculation widget when the value is "Fiction Goodreads starting package" and pass the calculation from the widget to the payment field.

Related Guide: How to Pass a Calculation to a Payment Field

The Form Calculation widget can be hidden.

Demo form: https://form.jotform.com/220111802049946

Feel free to clone it.

Related Guide: How to Clone an Existing Form From a URL

Great,

Is there an option in PayPal recurring payments to change the number of installment according to a certain field value?!

The number of recurring payments can't be changed with conditional logic. You can preselect the number of payments or you can allow your users to do it.

Related Guide: How to Setup a Recurring Payment Option