I received W2c from my employer, when I amend it says "We don't detect any differences between you original 2018 return and your amended return" but it is not true.
In the W2c, section 16 (state wages, tips and etc) is around $6k less than the original. why the software doesn't detect the change?
Since your changes were not federal, the 1040 doesn't change; ignore the message for federal only. To check your state:
Click State Taxes across the top. Depending on the state, you'll be able to manually adjust your wages somewhere.