This is down to Vodafone, any smartphone locked to a network never gets updates as fast as unlocked handsets. Vodafone will have gotten the updates but they test them first which can take months and then they need to optimise them to work on their phones and apps. It sucks I know and then they need to wait for them to be signed off before releasing them to the end user. So you will need to be patient and wait, they sometimes skip updates if not important too.
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