I 100% agree with Rodeo.
Only two possibilities exists here IMHO.
1) Google server is hacked and the information is changed.
This is very remote possibility as the hacker will not keep his name, address, contact info after the payment is issued. Why keep a trace?
2) Adsense password of OP is hacked and information is changed.
Again this is also a very remote possibility.
I handle 3-4 accounts for clients. I can change the address (within country) but I cant change the payee name. Also google is not asking for Bank information for Indian Publishers.
Also Changing country is impossible by simply logging into anyone's account.
Can you change back the Payee Name to your Name since you can log into your adsense account? If the answer is "No" then same case with the hacker who has (possibly) hacked your adsense password.
So I feel something is missing here or some misunderstanding.
Did you open the account yourself? Sorry for the obvious question but I did open adsense account for one of my overseas client with putting all his information.
If you have outsource this work to anyone there might be a possibility that he put his name while opening the account. Again this is very remote possibility but still there is a chance it might occur.
In India, Police are very strict about cyber crime and they take it very seriously.
If you want any help I am ready to help with Cyber cell of Police in india.
Website of Cyber cell in Mumbai,india.
[cybercellmumbai.com...] (Hope mods will keep this link.)