It depends on the network, which controls the length of the ‘unbonding period’--which is the time between when you request your assets to be unstaked and when those assets are actually unstaked by the network The unbonding period on Matic is approximately 9 days. This period applies to the originally delegated amount and re-delegated amounts - it does not apply to any rewards that were nor re-delegated. 

However, users with staked ETH cannot withdraw their staked assets from the Beacon Chain (ETH2 network) currently. You can learn more about ETH unstaking here.