Probably because you don't realize some of those Jeremiah verses are not for the times you speak of.
Please explain why not?
14 Therefore, behold, the days come, saith the Lord, that it shall no more be said, The Lord liveth, that brought up the children of Israel out of the land of Egypt;
15 But, The Lord liveth, that brought up the children of Israel from the land of the north, and from all the lands whither he had driven them: and I will bring them again into their land that I gave unto their fathers.
That above is put for the gathering of all... the tribes of Israel back to the holy lands of promise, both houses. At present, and for several centuries past, the ones that have returned are only a small remnant of the Jews of the "house of Judah", put for the three tribes of Judah, Benjamin, and Levi. Per 1 Kings 11 forward, only a small group of the northern ten tribes migrated south to join with Judah because of God splitting the kingdom and giving Jeroboam to rule over ten tribes in the north, called the "house of Israel". Those ten tribes of Israel are not being gathered today, they are still lost, even the Jews don't know where or who those ten tribes are today. But our Heavenly Father knows as He has shown in His Word.
So with those two above Jer.16 verses, that is the day of Christ's coming when He will gather all the tribes of Israel back together again in the holy land, believing Gentiles with them. That's when it will be no more said how God led Israel out of Egypt, but how He gathered Israel out of the nations where He scattered them, and brought them back to their own lands of promise. That event is also covered in Ezekiel 37 about the joining of the two sticks of Israel into one stick when Jesus comes.
16 Behold, I will send for many fishers, saith the Lord, and they shall fish them; and after will I send for many hunters, and they shall hunt them from every mountain, and from every hill, and out of the holes of the rocks.
Do you recall those who seek to hide from Christ on His appearing per the 6th Seal? That's about the unbelievers of Israel that rejected Him during this present world, even they will be gathered on that day.
Now the Jer.16:17-21 verses are for today, the end even, the tribulation time of affliction, and then God revealing Himself to them with Christ's coming.
In the next Jeremiah 33 chapter, God's Message about the gathering of Judah is continued, this time to include the ten tribes of Israel.
4 For thus saith the Lord, the God of Israel, concerning the houses of this city, and concerning the houses of the kings of Judah, which are thrown down by the mounts, and by the sword;
5 They come to fight with the Chaldeans, but it is to fill them with the dead bodies of men, whom I have slain in Mine anger and in My fury, and for all whose wickedness I have hid My face from this city.
6 Behold, I will bring it health and cure, and I will cure them, and will reveal unto them the abundance of peace and truth.
7 And I will cause the captivity of Judah and the captivity of Israel to return, and will build them, as at the first.
Notice how God marks both 'houses' in that verse with 1) "the captivity of Judah", and 2) "the captivity of Israel". In several places in the OT after God split ancient Israel into two separate kingdoms, the name 'Israel' was often only applied to the ten tribed northern kingdom, called after the split "house of Israel", "kingdom of Israel", "Samaria", "Ephraim", or just "Israel".
8 And I will cleanse them from all their iniquity, whereby they have sinned against Me; and I will pardon all their iniquities, whereby they have sinned, and whereby they have transgressed against Me.
9 And it shall be to Me a name of joy, a praise and an honour before all the nations of the earth, which shall hear all the good that I do unto them: and they shall fear and tremble for all the goodness and for all the prosperity that I procure unto it.
Those v.8-9 are also about the time after Christ's coming and their gathering back to the holy lands. It's certainly not for today, not with the tribulation of false idol worship at Jerusalem coming just around the corner. The coming tribulation time will be the worst example of false idol worship in Jerusalem that has ever been in the history of this world. The king of Babylon is coming once again, and it won't be Nebuchadnezzar like that one of Jeremiah's day.