How to Replace text partially in linux using sed : I have an xml tag that I need to manipulate on linux
<m1:PayloadId>TESTCASE01_0000123456</m1:PayloadId>
I need to change the text from "TESTCASE01_0000123456" to "TESTCASE01_1234567890" between the tags
I used the sed command in my code:"**sed -i 's/PayloadId>.*</m1:PayloadId>'0000123456'</g' t1.xml**" 
but it replaces the entire text. I need to retain "TESTCASE01_"
Appreciate any help

