Fatal error: Uncaught exception 'Propel\Runtime\Exception\PropelException' with message 'filterByEntity() only accepts arguments of type \Entity or Collection' in /home/offermob/public_html/demo1/model/Base/AttributeValueVarcharQuery.php:472 Stack trace: #0 /home/offermob/public_html/demo1/model/AttributeValueVarcharQuery.php(21): Base\AttributeValueVarcharQuery->filterByEntity(NULL) #1 /home/offermob/public_html/demo1/course.php(19): AttributeValueVarcharQuery->getAttrValUsingAttrAndEntity(NULL, Object(Attribute)) #2 {main} thrown in /home/offermob/public_html/demo1/model/Base/AttributeValueVarcharQuery.php on line 472