jain tirthankar were not belong ikshvaku dynasty?

Most Jain Tirthankaras did belong to the Ikshvaku (Ikṣvāku) dynasty.

• 22 of the 24 Tirthankaras are from the Ikshvaku lineage.
• The 20th Tirthankara, Munisuvrata, and the 22nd Tirthankara, Neminatha, are from the Harivamsha (Yadu/Lunar) lineage.
• Both Digambar and Shvetambar traditions agree on this point.

So the statement “Tirthankaras were not from the Ikshvaku dynasty” is incorrect; only two were not.