in the voting contract . then seeds should contain candidate but not poll_id.to_le_bytes().as_ref()

[ChiruDev3]

#[derive(Accounts)]
#[instruction(poll_id: u64, candidate: String)]
pub struct Vote<'info> {
    #[account(mut)]
    pub signer: Signer<'info>,

    #[account(
        mut,
        seeds = [b"poll".as_ref(), poll_id.to_le_bytes().as_ref()],
        bump,
    )]
    pub poll_account: Account<'info, PollAccount>,

    #[account(
        mut,
        seeds = [poll_id.to_le_bytes().as_ref(), candidate.as_ref()],
        bump)]
    pub candidate_account: Account<'info, CandidateAccount>,
}