What did you try or where did you ask?
Births are in Germany registered in the Standesamt/Registry office in the town or district where a person was born.
When you were born in Frankfurt am Main so the Standesamt there has to have your records.
Since not everybody can request records you will need to proof who you are and that you request the records for yourself.
Here are the information were to ask:
The links are in German, but google.translate or similar programs should help with a translation.
When you were baptized there could be also records in the parish registers. But for that also more information would be needed to find the right church.
When you need more assistance, a little more information would be good.
Dear Mr. Skinner,
Thank you for posting your request on History Hub!
You may need to contact different sources depending on a number of factors, including your parents’ citizenship and military status.
If either of your parents were in the U.S. military at the time of your birth, there may be a birth certificate or information that can be used to obtain one in your medical treatment folder. Medical Treatment Folders (clinical or inpatient, outpatient, dental records, and individual consultation service case files) of dependents of military personnel, civilian employees, American Red Cross personnel, and U.S. Merchant Marines, treated at U.S. military medical facilities are in the custody of NARA's National Personnel Records Center, (Military Personnel Records), 1 Archives Drive, St. Louis, MO 63138-1002. Please complete and mail a GSA Form 180 to request these records.
Due to the COVID-19 pandemic, the NPRC is closed except for emergencies. Currently, NPRC will continue servicing requests ONLY associated with medical treatments, burials, and homeless veterans seeking admittance to a homeless shelter. If your request is urgent, please see Emergency Requests and Deadlines. Please refrain from submitting non-emergency requests such as replacement medals, administrative corrections, or records research until NPRC returns to pre-COVID staffing levels. Please check archives.gov/veterans for updates to the NPRC operating hours and status. We apologize for any inconvenience.
In addition, if one or both of your parents are American citizens, you may contact the Department of State, Bureau of Consular Affairs for records relating to births after 1938, marriages after 1949, and deaths after 1974 of American citizens in a foreign country.
Finally, as Ms. Gorgas has noted, you may wish to contact the Standesamt/Registry in Frankfurt since German birth records are kept at the city or district level.
We hope this information is helpful. Best of luck with your family research!