Please note that the visa section can neither provide any information about the validity of your residence permit nor extend it. The only authority responsible for this is your Foreigners Authority, which you have to contact directly.
The visa section is also not authorized to forward applications for the extension of residence permits. Please contact the relevant immigration authority directly for assistance. If the immigration authority agrees to issue a “Fiktionsbescheinigung”, they may send this document directly to the Consulate to hand it out to you. Within the validity of this document, you may then return to Germany.
Please also note the following: As a general rule, German residence permits expire automatically (despite the mentioned validity date and also if issued as “permanent residence permit” (Niederlassungserlaubnis)) after a stay of more than six months outside Germany, the permanent residence permit EU (Daueraufenthalt-EU) allows you to be absent for up to 12 months. Some exemptions to this rule apply e.g. for holders of a permanent residence permit married to a German citizen. The alien authority in Germany may issue a confirmation about these exemptions on request. Please contact your immigration authority directly.
Under special circumstances, the immigration authority can grant longer absences. You cannot file such applications via the visa section Mumbai; you have to contact your immigration authority in Germany directly.