Recursive Block - Bad Access Exception

typedef void (^RetryAPICall)(BOOL isRetry);
- (RetryAPICall) makeRecursiveBlock
{
    RetryAPICall aBlock;
    __block __unsafe_unretained RetryAPICall aBlock_recursive;
    aBlock_recursive = aBlock = [^(BOOL isRetry)
    {
     [AFHTTPClient postPath:path
                 parameters:params
                        success:^(AFHTTPRequestOperationSKZ *operation, id responseObject) {
                //Execute success flow here
                    }
                        failure:^(AFHTTPRequestOperationSKZ *operation, NSError *error) {
                aBlockRecursive(YES); //This throws a bad access exception
                }];
    } copy];

    return aBlock;
}