There are three Credit Reference Agencies (CRAs) in the UK - Equifax, Experian and TransUnion. They all have different scores but this is completely normal. All three are dedicated to collecting information on your financial behaviour and how it has impacted your score.
It’s good practice to look at all of your credit scores on a regular basis so you can keep an eye on any changes. You can get to know your credit score better with free credit reports using the links below.