Thanks for your review.
We responded in full to your enquiry on 16th May although we note your enquiry came from a different email address to your order. It is possible your spam filter collected the response.
Anyhow, the response was as follows...
Hello
Thanks for your enquiry.
As the product is not chemical-based, it can take longer to work than chemical-based insecticides particularly if there is a heavy infestation.
As you have just completed the 8 consecutive days, for the time being, we would recommend increasing to 2 to 3 times a week thereafter until the infestation drops when you can then return to once weekly.
To deal with the issue more quickly, it would help to treat the coop (as well as the birds) with a product like the one below. Whilst you are correct that the mites have nothing to feed off in the coop, using a product in the coop will help accelerate the process as the mites are dealt with both on and off the birds.
https://www.aviform.co.uk/mitey-x-stuff-red-mite-powder-for-poultry-birds/
Hope this helps but happy to assist further as required.
Kind regards
Robin