Your post was blank @GnaneswariP5176 and the subject line seems to be truncated so your issue/question isn't really clear.
If you want assistance from the Community Forum then you need to explain/describe your issue/question clearly.
What exactly do you mean by "top up my balance"?
What exactly are you trying to buy?
Membership plan, add-ons, cash credit?
What happens when you try here?
Any error messages?
When were you last able to successfully buy stuff on 48?
If you need to contact 48 support about this then see the links in my signature below.
