Bold washing powder, and vinegar in place of fabric softener worked for me when I lived in the UK.
Now I can't get Bold, I find that pods smell nicest, I liked the smell of the ones my SIL uses so I found a local alternative. I can't remember what the UK one was, but this is the one I found which is in the same box, so probably equivalent. https://www.dm.de/spee-colorwaschmittel-caps-power-p4015200031521.html
And yes to the unstoppables, they are probably awful and cost a ridiculous amount but I buy a couple of bottles when they are on offer. You have to use more than I'd want to.
Don't use extra rinse on the machine, as it rinses out more of the scent. If you have sensitive skin, you probably can't really do the extra scents (try the vinegar trick instead).
You need to get the washing out as soon as it's finished, don't leave it in the machine for hours. And dry quickly. So tumble dryer or outside on a sunny or windy day, or airer but with lots of space between stuff so it isn't hanging around damp. The tower or balcony shape airers are best for this.
And clean out your washing machine filter. If you're getting a vague smell of stale socks, it's probably the filter.
Do a hot wash every few weeks in the machine (60+) and include anything that has a smell that doesn't wash out.
Do a cleaning cycle (90 degree wash, only vinegar or soda crystals) once every 6-12 months. Probably more frequently if you wash with lots of liquid type detergents.