GarageBand and iPhone SE: Microphone input level control?

New Garageband for iPhone user here, installed it on my iPhone SE gen3 and ran into a problem immediately.

What I want to do is be able to record using the phone’s internal microphone for situations like practicing at home, at rehearsals and during live performances then export the recordings to Logic running on my Mac for editing.

The User guide for version 2.3.18 says this about using the Audio Recorder:

“Adjust the microphone input level 

The In level slider on the left shows the input level from the microphone or input source. If your iPhone or input source supports input level control, the slider is active and you can drag it up or down to adjust the input level. "

I’ll assume my iPhone SE gen 3 does not support input level control, because I cannot use it.

How am I supposed to do to deal with varying sound levels while recording? Is there an automatic level control feature like those found on most pocket recorders?

My setup:

iPhone SE gen 3 (MMX42V6J4G), iOS 26.5, Garageband 2.3.18