The customer authorization (provided in the link you clicked) is out of date, and does not entitle you to use the Blended Threat service.
https://www.dccae.gov.ie/en-ie/natural-resources/legislation/Documents/48/Conservation%20of%20Salmon%20and%20Sea%20Trout%20(River%20Slaney)%20Bye-law%20No.%20970,%202018.pdf