Hi all Sifu,
Seeking some advise here. I change phone.. iphone and my Grab apps can no longer be use. Wierd was that i can receive , top up money BUT i can notnuse it to pay or transfer/send money to ither Grab users.

I tired:
Uninstall Grab App from new phone device and reintall
Signed out and sign in.
Refresh cache from safari of the phone and clear data
Call Grab center and they said they already aware my phone devise change and no problem at their end.

But now, i still not able to pay or send money. Its just gave me a statememt that the transaction was unsuccessful and try again later.

its working now. Apparently, Grab, if you switch phone, it will take 24hrs to be effective. You can still receive money, but you can only pay after 24hr after switching.
Thank you all.