Syntax for shell script to Delete the lines containing the pattern

I am trying to delete the lines in the file which contain "Memo" whether it is a upper or lower case. Can you please let me know what is the command to delete lines in the file before loading into the table. I tried using the below command but it did not work:

sed '/Memo/d' GDPUJ*.GLI - I am getting error: "?Invalid command"

mget GDPUJ*.GLI
sed '/Memo/d' GDPUJ*.GLI
mdelete GDPUJ*.GLI
quit
END_SCRIPT