You are missing the input element for your action class. You should correct as follow:
<action name="customerpay" method="execute"
class="com.programcreek.struts2.CustpayAction">
<result...
Type: Posts; User: ha.minh.nam
You are missing the input element for your action class. You should correct as follow:
<action name="customerpay" method="execute"
class="com.programcreek.struts2.CustpayAction">
<result...