this is a validation message. Cost Center is mandatory, you must fill that…
Chart of Account associated with “Profit and Lost Statement” must have cost center.
Account Type “Expense Account” and “Income Account” must have cost center.
for your case:Telephone Expenses - SNN → Account Type “Expense Account” and Associated with “Profit and Lost Statement”
Thank you very much for you valuable input @komsel2228 and @Pawan. This was rather a naive question. However, I think it would be very helpful for rookies if its put in the manual. such small things really make a big difference.