The total number of eclipses is limited to seven or fewer per year because one condition that must be met for a lunar or solar eclipse is that:

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For a lunar or solar eclipse to occur, the Moon must be close to or crossing the ecliptic plane, which is the plane of Earth's orbit around the Sun. If the Moon's orbit was perfectly aligned with Earth's orbit, we would see a lunar eclipse every full moon and a solar eclipse every new moon. However, the Moon's orbit is tilted with respect to Earth's orbit, so eclipses only occur when the Moon crosses Earth's orbital plane at the same time that it is in the right phase (full or new). This alignment happens only a few times per year, which limits the total number of eclipses to seven or fewer.

The Total Number of Eclipses Is Limited to Seven or Fewer