refund for some insurance changes but then gone up when looking to renew

my boyfriend has recently passed his test and wanted adding to my insurance weve also recently moved in together. Added him to my insurance as a named driver and changed my adress and got a refund of £21 as i pay my insurance yearly. My insurance is due next month thought id have a look for an estimate on what it would be done the same thing of adding my boyfriend putting my new adress in other than that theres been no changes whatsoever and my insurance is apparently going to be £2,100 for the year ( i paid £1,700 last time for the year) does anyone have any idea why this could be:)
this was all today btw