We are told that Belshazzar got to know & elevated Daniel the night of his death In Daniel 5.
Daniel 5:13,29-30 NASB
Then Daniel was brought in before the king. The king spoke and said to Daniel, "Are you that Daniel who is one of the exiles from Judah, whom my father the king brought from Judah? Then Belshazzar gave orders, and they clothed Daniel with purple and put a necklace of gold around his neck, and issued a proclamation concerning him that he now had authority as the third ruler in the kingdom. That same night Belshazzar the Chaldean king was slain
. But in Daniel 8 it is said Daniel was going about the kings business in the third year of his reign.
Daniel 8:1,27 NASB
In the third year of the reign of Belshazzar the king a vision appeared to me, Daniel, subsequent to the one which appeared to me previously. Then I, Daniel, was exhausted and sick for days. Then I got up again and carried on the king's business; but I was astounded at the vision, and there was none to explain it.
How could Daniel have been in the service of king in his third year when he only got to know him for just one night,just before the king's death?
Could there be a chronological issue here?