Came across this issue when selecting a customer on a sales order, using the Customer Name field.
For some reason, if I select a customer using Customer Name, notifications do not show up for e.g. Overdue Balance, Credit Limit etc. This only happens if, under the General tab, I have expanded it to 'Show More'.
Workaround -> If I minimise that Fasttab, so only Customer Name is showing rather than Customer No then the notifications do show up. However, if I need to change the customer on the sales order, then when I use the Customer Name field again, the notifications don't show up or update.
I know you can search the name of the customer using the Customer No field but it just seems odd that this is happening.