My i94 expired recently but my extension is approved till 2022. Can I travel to India through Frankfurt? I will be going for stamping when I go to India.
According to Germany's Airport Transit Visa requirements document (dated April 2019), it looks like you can transit through Frankfurt if you meet one of the exception conditions (mentioned only relevant ones, refer doc for full list of exceptions):
they hold a used valid or expired visa issued by the USA and return from the USA and travel to a non-Schengen Member State within 24 hours after the expiration of their visa, or
they hold a valid visa for a Schengen Member State, Bulgaria, Canada, Croatia, Cyprus, Ireland, Japan, Romania or UK, or
they hold a used valid or expired visa issued by Bulgaria, Canada, Croatia, Cyprus, Ireland, Japan, Romania or UK and return from the country of visa issuance and travel to a non-Schengen Member State.