I797 Approved in April 2020 but expiring in 31st December 2020

Dear Community,

Hope you are doing good !!

need help to explore what option I have now.

from India I applied my H1B Cal exempt that i797 got approved in April 2020. but I got to know in October that petition validity is from April 2020 to 31st December 2020 only.

now due to travel ban I can’t stamp and fly to extend it.

What is the option I have now ?
can I do extension from here in India ? if yes then is it going to take same time or it will be faster ?

Please help me.

Thank you