2 Chronicles 28:16 (KJV)

Did the king of Assyria help Ahaz?He took Damascus and slew Rezin, as Ahaz asked; but he made Ahaz his vassal, took his treasures, and left him to the Edomites and Philistines: Ahaz was distressed, not strengthened.

The wicked reign of Ahaz in JudahIsrael gained this victory because God was wroth with Judah, and made them the rod of his indignation. He reminds them of their own sins. It ill becomes...

2 Kings 16:7 So Ahaz sent messengers to Tiglathpileser king of Assyria, saying, I am thy servant and thy son: come up, and save me out of the hand of the king of Syria, and out of the hand of the king of Israel, which rise up against me.

From Thompson’s Chain-Reference Bible (1908).

2 Kings 16:5–7 Then Rezin king of Syria and Pekah son of Remaliah king of Israel came up to Jerusalem to war: and they besieged Ahaz, but could not overcome him. …
Isaiah 7:1–9 And it came to pass in the days of Ahaz the son of Jotham, the son of Uzziah, king of Judah, that Rezin the king of Syria, and Pekah the son of Remaliah, king of Israel, went up toward Jerusalem to war against it, but could not prevail against it. …
Isaiah 7:17 The LORD shall bring upon thee, and upon thy people, and upon thy father's house, days that have not come, from the day that Ephraim departed from Judah; even the king of Assyria.

From OpenBible.info, most relevant first.

AhazPossessor. (1.) A grandson of Jonathan (1 Chr 8:35; 1 Chr 9:42).
AssyriaThe name derived from the city Asshur on the Tigris, the original capital of the country, was originally a colony from Babylonia, and was...

At that time בָּעֵת bāʿēt עֵת Noun · masculine or feminine singular · with preposition with the הַהִיא hahîʾ Pronoun · third person feminine singular · with the
did king הַמֶּלֶךְ hammelek מֶלֶךְ Noun · masculine singular · with the
Ahaz אָחָז ʾāḥāz אָחָז Proper name
send שָׁלַח šālaḥ שָׁלַח Verb · qal perfect, third person masculine singular
unto the kings עַל ʿal Preposition מַלְכֵי malkê מֶלֶךְ Noun · masculine plural construct
of Assyria אַשּׁוּר ʾaššûr אַשּׁוּר Proper name
to help לַעְזֹר laʿzōr עָזַר Verb · qal infinitive construct · with preposition לוֹ lô Preposition · with suffix: third person masculine singular

2 Chronicles 28:16 KJV