Liquibase modifySQL parse error

Hello, I am new to JMix and just starting to setup my data model. I am getting the following error when starting the application:

[2021-09-15 17:07:13] SEVERE [liquibase.parser] cvc-complex-type.3.2.2: Attribute ‘a’ is not allowed to appear in element ‘append’.

Here’s the offending XML (Look at the modifySQL):

    <modifySql>
        <append a="75109387347912" b="applyToRollback" value="where DELETED_DATE is null"/>
    </modifySql>
</changeSet>

Check the answer here