Lost phone need a new sim with same number

Try the steps in the following help article:

What to do if your SIM card gets lost or stolen | SMARTY Help Centre

Ah, that's frustrating FionaTh_1076694. 
I guess you'll need to ask for a replacement SIM using the SMARTY online web chat support team. The support team work 8am - 8pm daily.
Access web chat from the icon bottom right of your screen, when you're signed-in to your online dashboard.
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