& welcome to the giffgaff Community
Once you have the SIM you will need to perform the SIM Swap. Carrying out the SIM swap will transfer your current number, airtime credit and/or bundle (goodybag) over to new SIM. The SIM swap should take no more than 30 minutes to complete and can be performed any time between 4.30am and 9.30pm.
Please check out this
from member flaxvert.