Hi @Shobhna Dhami ,
The issue is caused due to the fix in AMBARI-22952.
You can resolve this by :
1) stop ambari-server
2) run command : refer : accept GPL license
ambari-server setup --enable-lzo-under-gpl-license
3) start ambari-server
and try again.
Please let me know if this doesn't worked.
Please accept answer if it did