Reviving an old SIM

[martyncadmaster]

I have an old phone with a PAYG sim that has not been used for some time - I now want to put the SIM in another phone and top up the PAYG, how do I do this?

I also have a 5G outdoor hub on contract and whenever I try to contact Three, it defaults to this.

[Geluk]

If number not used for last 180 days, number will be lost/ reallocated.