30 days from the last check should be sufficient.
It's worth asking @Stephers
We’re just customers like you but it sounds like you’ll need someone to access your account which can’t be done from here. If you message O2 on Facebook (https://o2uk.co/O2CFB) , Twitter (https://o2uk.co/O2CTW) or Instagram (https://o2uk.co/O2CIG) , they should be able to help you with this
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