Locations for IP addresses on online tools are pretty useless apart from the country that they are in, down to town level all it will show is where the ISP’s either registered it or where their main operation/gateways are located. For example I have a static IP address from my ISP and I’m located in Wales, yet if you look up that IP it’ll show as Sheffield (easy guess who the ISP is!)
The larger ISP’s will have multiple ranges to cope with the number of users and thru acquisition of other ISP’s thru mergers and so on.
With a dynamically allocated IP address all it needs is a reset/reboot of your router or perhaps a line drop, noting that any of this can occur at anytime so you might not have noticed unless you were using the internet at the time of the drop/reboot/reset for you to loose the current allocation and your router to re-login in to the ISP’s network and get allocated a new address. OR for the ISP to be doing some planned work/re-engineering and tinker with their gateways and introduce a new range or shift you onto a new range.
I think it’s Kudos to the bank for noticing something outside of your normal pattern of usage and doing something about it, perhaps with a reduction for not notifying you straight away.