A great starting place for the minimum information to gather to fulfill the Know Your Client obligation (and to provide competent financial advice or financial planning) was developed by the UK financial advice regulator, the FCA. Here is the tool: https://www.fca.org.uk/publication/forms/advice-assessment-tool-ria-riaat.xlsx
Did your advisor ask explore your financial circumstances? Did your advisor use empirically sound, behavioural assessment tools to challenge your unwitting self-diagnosed assessment of investment knowledge, investment objective and (crucially, risk tolerance? If your advisor didn't learn this information about you, didn't use tools to go beyond your self-assessments, and you lost money, then you may have a claim to recover your losses.
If you are self-advising, then this information should be central to your own investing process. You will have to modify this tool for personal use.
For further information see: https://www.fca.org.uk/firms/retirement-income-advice-assessment-tool-riaat