Box 12b on my w-2 has CC code in box. When looking at drop down code box there is no CC code?

Code CC is not a valid code for box 12.  Contact your employer to get a corrected W-2.
Valid Codes -
A—Uncollected social security or RRTA tax on tips. Include this tax on Form
1040. See “Other Taxes” in the Form 1040 instructions.
B—Uncollected Medicare tax on tips. Include this tax on Form 1040. See
“Other Taxes” in the Form 1040 instructions.
C—Taxable cost of group-term life insurance over $50,000 (included in boxes
1, 3 (up to social security wage base), and 5)
D—Elective deferrals to a section 401(k) cash or deferred arrangement. Also
includes deferrals under a SIMPLE retirement account that is part of a
section 401(k) arrangement.
E—Elective deferrals under a section 403(b) salary reduction agreement
F—Elective deferrals under a section 408(k)(6) salary reduction SEP
G—Elective deferrals and employer contributions (including nonelective
deferrals) to a section 457(b) deferred compensation plan
H—Elective deferrals to a section 501(c)(18)(D) tax-exempt organization
plan. See “Adjusted Gross Income” in the Form 1040 instructions for
how to deduct.
J—Nontaxable sick pay (information only, not included in boxes 1, 3, or
5)
K—20% excise tax on excess golden parachute payments. See “Other
Taxes” in the Form 1040 instructions.
L—Substantiated employee business expense reimbursements
(nontaxable)
M—Uncollected social security or RRTA tax on taxable cost of groupterm
life insurance over $50,000 (former employees only). See “Other
Taxes” in the Form 1040 instructions.
N—Uncollected Medicare tax on taxable cost of group-term life
insurance over $50,000 (former employees only). See “Other Taxes” in
the Form 1040 instructions.
P—Excludable moving expense reimbursements paid directly to
employee (not included in boxes 1, 3, or 5)
Q—Nontaxable combat pay. See the instructions for Form 1040 or Form
1040A for details on reporting this amount.
R—Employer contributions to your Archer MSA. Report on Form 8853,
Archer MSAs and Long-Term Care Insurance Contracts.
S—Employee salary reduction contributions under a section 408(p)
SIMPLE plan (not included in box 1)
T—Adoption benefits (not included in box 1). Complete Form 8839,
Qualified Adoption Expenses, to compute any taxable and nontaxable
amounts.
V—Income from exercise of nonstatutory stock option(s) (included in
boxes 1, 3 (up to social security wage base), and 5). See Pub. 525,
Taxable and Nontaxable Income, for reporting requirements.
W—Employer contributions (including amounts the employee elected to
contribute using a section 125 (cafeteria) plan) to your health savings
account. Report on Form 8889, Health Savings Accounts (HSAs).
Y—Deferrals under a section 409A nonqualified deferred compensation
plan
Z—Income under a nonqualified deferred compensation plan that fails
to satisfy section 409A. This amount is also included in box 1. It is
subject to an additional 20% tax plus interest. See “Other Taxes” in the
Form 1040 instructions.
AA—Designated Roth contributions under a section 401(k) plan
BB—Designated Roth contributions under a section 403(b) plan
DD—Cost of employer-sponsored health coverage. The amount
reported with Code DD is not taxable.
EE—Designated Roth contributions under a governmental section
457(b) plan. This amount does not apply to contributions under a taxexempt
organization section 457(b) plan.
FF—Permitted benefits under a qualified small employer health
reimbursement arrangement

Sounds like the payroll company that created the W2s made a mistake on the letter coding. Time for a call to your employers payroll processor.