"Serial Nos Required for Serialized Item" in POS

Dear all,

I have set an item with serial/batch number. In the search form I input the serial to sell (it worked) but when I click payment & print invoice: Serial Nos Required for Serialized Item XXX

My version:
ERPNext: v12.6.0 (version-12)
Frappe Framework: v12.4.1 (version-12)

Do you have any solutions for this? Thank you.