Instance 1
In IdentityStaking.sol, self-stake or community-stake lock duration can be extended. However, checks are insufficient and allow a new lock to have the same unlockTime as the old lock.
https://github.com/code-423n4/2024-03-gitcoin/blob/6529b351cd72a858541f60c52f0e5ad0fb6f1b16/id-staking-v2/contracts/IdentityStaking.sol#L273
Instance 2
https://github.com/code-423n4/2024-03-gitcoin/blob/6529b351cd72a858541f60c52f0e5ad0fb6f1b16/id-staking-v2/contracts/IdentityStaking.sol#L371
Change to unlockTime <= selfStakes[msg.sender].unlockTime to ensure new locktime will be different.
