Canon EOS 7D Mark II (G) Instruction Manual page 503

Movie shooting stops by itself.
If the card's writing speed is slow, movie shooting may stop
automatically. For cards that can record movies, see page 5. To find
out the card's writing speed, refer to the card manufacturer's website.
If the movie shooting time reaches 29 min. 59 sec., the movie shooting
will stop automatically.
Movie Servo AF cannot be used.
The movie recording size is set to L 8(59.94 fps) or 7(50.00
fps).
The ISO speed cannot be set for movie shooting.
If the shooting mode is <A>, <d>, <s>, <f>, and <F>, the
ISO speed will be set automatically. In the <a> mode, you can freely
set the ISO speed (p.321).
The manually set ISO speed changes when
switching to movie shooting.
If you shoot a movie with manual exposure set to H2 (equivalent to
ISO 51200), the ISO speed setting will switch to H1 (equivalent to ISO
25600). Even if you switch back to still photo shooting, the ISO speed
will not revert to the H2.
The exposure changes during movie shooting.
If you change the shutter speed or aperture during movie shooting, the
changes in the exposure may be recorded.
Zooming the lens during movie shooting can cause changes in the
exposure regardless of whether the lens's maximum aperture changes
or not. The changes in the exposure may be recorded as a result.
Troubleshooting Guide
503