hi again (Accra)

last week i charged the credit for 1 month,but today my credit finished...and i talk only 2 times this week with video call on messenger...im so sad...thanx for ur advice....but i have to pay another credit?its true that if im using voice call on yahoo messenger ,my credit its going more faster....?what its the best option to be able to have internet home but to can have video call on mess as well ,without finishing my credit too fast ?.thanks a lot