VFD 300 brightness doesn't seem to adjust

[jm407861]

My VFD 300's brightness adjust slider doesn't do anything. I can't see the screen when outdoors in sunlight.

[BandOfBrothers]

That’s weird @jm407861

Ive not used your version of Vodafone mobile phone but does it have auto brightness settings ? If so try turning that Off then try manually adjusting the screen brightness. 

Some phones however do struggle in some outdoor conditions. 

Try turning the phone Off and On to soft reboot it. 

[hrym]

I think the OP is talking about manual adjustment.   It may be that the screen simply doesn't have the oomph for bright sunlight (some don't), but it would be worth enabling auto brighness just to see if that makes any differfence.