MSCRM changes didn't reflected on the target environment

Hello All Experts,

I have imported one managed solution onto the target environment with enabling notes(attachment) option from the entity.

Although i am doing upgrade with override customization on target environment, but why this entity is not reflecting the changes.

if i directly change on the target environment then it will become unmanaged customization and which i don't want to do.

any help will be appreciable.