@vancouverislandhiker
You may not have injected it correctly. That recently happened to me. I thought the medicine needed reformulated so I went back and had the doctor inject the same dose and thought I wasn't injecting it coyand he was right. When he injected it all was fine. You might want to try that or try the versions that goes in the urethra or the topically applied one. I understand the last two don't work quite as well as the injections but might be worth a try.
Take care,
Jake