A had given personal guarantee as a trustee of the trust that had mortgaged its property to the bank. The bank sold the property and enforced balance dues on A. A and his wife B owned a joint property but A sold his shares to B. And B after becoming the sole owner sold the property to x. 

Can bank attach that property now owned by x who has no connection with A or B. Also B is in now way connected with dues or guarantees given by A.

Can banks attach properties which were once jointly owned by A. Banks gave notice much later after sale.

Any transfer that is colourable and is meant or motivated to defeat the claims of a creditor is voidable at the option of the creditor, in simple words - the bank can trace your half share in the property for satisfaction of their claims.