حج is واجب once. Repeat حج is permissible but contemporary scholars debate its advisability when millions await their first opportunity.
حج is واجب once in a lifetime. Additional حج is voluntary (nafl) and carries significant reward. نبی کریم was asked about performing حج every year and indicated it is meritorious but not required.
However, with millions waiting for their first حج, many scholars argue repeat حجاج should give way to first-timers. Saudi Arabia now officially prioritizes first-time applicants, and some countries restrict repeat applications within five years.
A balanced approach: if your repeat حج does not deprive another Muslim of their first opportunity and your finances allow it, voluntary حج is blessed. But yielding your slot to a first-timer may carry even greater reward.
Source: Ibn Qudamah, Al-Mughni; International Islamic Fiqh Academy