Ladbrokes complaint: Data Protection

On 15th March 2022 I entered the Ladbrokes shop in Morpeth as normal regular customer. I quickly inform by a member of staff that was i was barred. I questioned why and was told it was because of the level of my bets. I found this strange because the staff member knows nothing about me, my income or personal wealth. I did question why they were telling me an not the manager but I got told it didn’t matter who told me and there would be a letter ing why I was barred….to this day I’ve not received anything! Anyhow, I left the premises never to return.
Since that day I’ve been told that my personal details including my photo have been circulated around all the Ladbrokes and Coral shops…. I need to understand under the data proportion act why Ladbrokes still have this on file. I understood that once any self exclusion had expired all data relating to an individual was deleted….obviously not the case!
Also, more importantly, today I’ve been approached by a friend who doesn’t gamble and never entered the Morpeth shop that he has been told by a Ladbrokes member of staff that I was barred for being abusive and aggressive whilst playing the FOBT’s. The individual also s that he’s read the reportletter!
Obviously I’m not only upset to learn this from a friend but I’m angry that someone is discussing my personal information without my consent or knowledge.
As a result of what I see as a breach of my personal data and the embarrassment this has caused me i will seek legal advice. I will also seek a witness statement.