Hi
I have unclaimed BCHA (now eCash) sitting in my Android mobile Bitpay wallet, but I can't find the private keys of the address, how to do that ?
Whenever I try it takes to a private key encoding my wallet, not a specific address.
Did you contact the support before post here ? There should be a support on how to extract the private keys.
If you are willing to get BCH from 2017 bitcoin fork, i think it would be a little bit harder, as new bitpay client versions don't seem to support the fork ad old versions will be hard to use if you lost access to it (no seed, no passord...)
Private keys in BitPay are encrypted by the password you set, you should be able to decrypt them using the same password. And bsed on your description, you seem not having the password anymore of your old wallet.
This link should be helpful for you :
https://bitpay.com/blog/private-key-security/