What if box 12a, 12b, and 12c have a code, but no amount?

[aljamora]

My 12a, 12b, and 12c all have a code that corresponds to something on the list, but there is no amount listed next to the codes. What do I do?

[PaulaM]

Contact your employer for the amounts that should be listed next to the codes. This is required data and the employer should issue you a corrected form.

https://ttlc.intuit.com/questions/1899457-what-do-all-the-letter-codes-in-box-12-of-my-w-2-mean