My navy blue client logo printed purple on 500 shirts and now I'm out $1,200

Had the same thing happen with a client's royal blue on a 300 piece order back in 2019, came out looking like a sad lavender. What finally worked was switching to a real spot color match, cost me about 80 bucks extra on the setup but the shirts were dead on. For dark blues that CMYK build is a gamble because the printer's profile can shift it way off without you knowing. If the job is over 100 pieces, just eat the spot color fee, it's way cheaper than a reprint.