If you do not renew your certificate by midnight of the expiration date, your certificate becomes delinquent and you cannot work as a CNA until the certificate is renewed. In order to renew your license after the expiration date, you will need to meet the work and in-service training requirements, pay the original renewal fee and pay a delinquency fee. If the certificate is not renewed by expiration date,  two years later, your certificate will become null and void and you will have to take the CNA examination again to be certified in Florida.