O2

I have upgraded from a Pay As You Go sim to a monthly contract which activated today.The number is the same.I had £25 outstanding credit on my Pay As You Go account and understood that this should be credited to my new contract.How will this credit b...

I currently have a pay as you go 4G sim in my iPhone 11 Pro. I will soon be upgrading to an iPhone 12 pro with 5G. Do I need to update my sim from 4G to 5G and what is the process?