If you will review the Lord's application of restraint against Satan and his angels over time you can know that the same increases over time from the pre-flood days
The Lord stopped the interaction of some of the fallen angels with the daughters of men and reduced angelic interaction with humans to one of influence only [Daniel 10]
Hence no more off spring [the giants of the pre-flood era] .... these were all destroyed in the flood
And the pre-flood fallen angels were sent to the abyss awaiting the judgment of the coming Day of the Lord [Jude 1:6]
Next the Lord applied more restraint against the balance of free fallen angles including Satan .... these are still active, have access to heaven, and can and do influence humans, but cannot interact with them
This increase in the level of restraint is the same today and was instituted at the Lord's first advent in the first century
The time is coming when this setting will change and is related to the Lord's judgment of the tribulation .... the Day of the Lord
Human intransigence against the Lord will reach a condition unacceptable to Him and He will release restraint and allow for Satan and the fallen angels to come to the earth and directly interact with a lost world of humanity [Revelation 9]
At the same time He will ban all of them from heaven and sequester them upon the earth where He intends to allow them to vex and kill un-repentant humans during the tribulation
And He will also remove restraint to the extent for allowing Satan to bring His "antichrist" to rule on the earth for a short period of time [Daniel 7:7-25; 8:9-25; 9:26-27 [the other prince that will come]; 11:36-45; 12:1-7; Thessalonians 2:8-12; Revelation 9:11; 11:7; 12:12; 13:1-4; 17:8-18;]
Then He will eventually kill them all in His lake of fire [Jude 1:6; Revelation 19:20; 20:10; 20:11-15]