diff --git a/htdocs/install/mysql/migration/9.0.0-10.0.0.sql b/htdocs/install/mysql/migration/9.0.0-10.0.0.sql
index a7f810ac508..ff4dbd32fa7 100644
--- a/htdocs/install/mysql/migration/9.0.0-10.0.0.sql
+++ b/htdocs/install/mysql/migration/9.0.0-10.0.0.sql
@@ -159,7 +159,7 @@ INSERT INTO llx_c_units (code, scale, label, short_label, unit_type, active) VAL
 INSERT INTO llx_c_units (code, scale, label, short_label, unit_type, active) VALUES ('H','3600','hour','h', 'time', 1);
 INSERT INTO llx_c_units (code, scale, label, short_label, unit_type, active) VALUES ('D','86400','day','d', 'time', 1);
 INSERT INTO llx_c_units (code, scale, label, short_label, unit_type, active) VALUES ('W','604800','week','W', 'time', 1);
-INSERT INTO llx_c_units (code, scale, label, short_label, unit_type, active) VALUES ('M','2629800','month','m', 'time', 1);
+INSERT INTO llx_c_units (code, scale, label, short_label, unit_type, active) VALUES ('MO','2629800','month','m', 'time', 1);
 INSERT INTO llx_c_units (code, scale, label, short_label, unit_type, active) VALUES ('Y','31557600','year','Y', 'time', 1);
 
 -- Default Warehouse id for a user