[Userform] Inserted details disappear after msg box pop up

I created a userform which users need to enter some text boxes and choose from combo boxes.
Some are mandatory, so I decided to use message boxes as reminders when click the "Create Record" Button.
As there are so many fields, I want to put them all in a sub then can simply call in other private sub as well.

But there is a problem that all the inserted data will be gone after any one of the msgboxes.

e.g. I have 10 text boxes and 3 combo boxes are mandatory, I forget to fill in one, and msg box pop up, after closed the msg box, all the other 12 fields have been cleared. It is not user-friendly, so I want to remain all the filled text or the chose option in the combo box

My questions:
1. how can I write to solve this situation?
2. is it possible to write all in one sub?

Thank you

see big yellow banner at head of page - how to upload your workbook.
help us to help you with an appropriate answer.

There are many ways to do what you want, taking advantage of the power of the UserForm including:
a. Use a Status Label in the UserForm, instead of a MsgBox - use Red Font (ForeColor) when there is an error.
b. Hide the "Create Record" CommandButton until all prerequisites are met.
c. Color the Controls (TextBoxes, ComboBoxes) in red, when the prerequisite is not met.

Like torachan said, if you upload a small sample file, with your existing code, we can do a better job of helping you.

Lewis