hey @shubhamnyaik
Try this:
index=your_index | rex field=_raw "<(businessChannel|ns1:businessChannel)>(?P<businessChannel>[^\<]*)"
let me know if it helps!
Also, your log does not contain this fields please give us proper sample log.
@shubhamnyaik, you would need to post your data using code button 101010
here on Splunk Answers so that special characters do not escape.