To change your budget allocation for next month you have to do the following steps:
Open the NAVIT app (make sure it's updated to the latest version).
Go to the settings.
Tap on 'Allocate Budget'.
Select the card where you want to assign your budget for the next month, and confirm your selection. Make sure to allocate all of your budget.
Divide the budget among the cards or allocate it as you prefer, and confirm your final allocation.
Please note that the budget allocation applies to the new budget you will receive next month, not the budget you currently have. Please also be aware that after your account activation if you don't allocate your budget to any module you won't receive any, so please always make sure that your Budget allocation is done.