MacBook Pro Touch Bar

dazia64 wrote:

accidentally turned down brightness on mac book pro Touch Bar how do I get it back up

The Touchbar has no independent brightness—

typically it indicates a hardware issue.

Use Apple Diagnostics to test your Mac hardware—

Use Apple Diagnostics to test your Mac - Apple Support

In or out of warranty you can get a free over the counter 'Apple Service Diagnostics' test /assessment

Make an appointment for a "hardware issue"

Genius Bar Reservation and Apple Support Options - Apple

Outside the USA

Contact Apple for support and service - Apple Support

If software on an Intel Mac you can try both:

resetting the SMC Reset the SMC of your Mac - Apple Support see the details.

resetting NVRAM/PRAM Reset NVRAM on your Mac - Apple Support

no insight— you can try reinstalling the macOS

How to reinstall macOS - Apple Support

no resolve, last ditch effort if software

Revive or restore an Intel-based Mac using Apple Configurator - Apple Support (CA)