Over lockdown, I've been growing peppers and chillies from seeds on my windowsills - they've been brilliant, but I'm finding at the moment that they're covered in greenfly, so all the flowers are dropping off, and they're growing all misshapen. I've tried spraying them with a solution of washing up liquid, which made no difference at all. I left them outside for a few hours and the bugs disappeared, but returned within a couple of days when I brought them back in. Help! What am I doing wrong? The house is clean and hoovered, where are they coming from, and how do I get rid of them?