HRMC TAX CRACKDOWN SIDEHUSTLES

( UK Based )So apparently HRMC have invested a large capital to investigate everyone with a side hustle on ETSY, Shopify, eBay etc. I am an ESTY seller and my profit margin are already slim as I already being charged taxes on every sales from the platform. The payments go directly into my account from ETSY. I also work full time and I conscious HRMC might reach out with a fine. What are your thoughts on this? Is this true? What can be done? Any help can be appreciate it to shed some light on this. Thanks in advance