Start with GOV.UK, which explains the rules and lists the authorised tenancy deposit schemes for England and Wales. The relevant scheme’s own website can confirm whether a deposit is protected and explain its dispute process, while forums, blogs and landlord guides may be incomplete or out of date. Scotland and Northern Ireland have different arrangements, so check the appropriate devolved government website. If you think your deposit was not protected or you did not receive the required information, Citizens Advice, Shelter or a solicitor can help you understand your options.