When your Asset realisation is not being reflected in the Cashflow Forecast, even though there is a budget line for the realisation of an Asset.
Check the Cashflow setting for the specific Asset account:
Budgets & Cashflow > Cashflow Settings > Cashflow Forecast > Advanced Settings
Then search for the specific account
Check the settings on the account
To ensure the bank account movement is reflected in the period the movement is budgeted, set to Profile and 100% current.