Hi Cheng, Vikki ,
Welcome to Microsoft Q&A platform and thanks for posting your query here.
I understand that you are trying to download the zip file using ADF/Synapse pipelines using HTTP connector ( binary format) , however it's not working when the alphanumeric characters are present in URL but it's working fine when ID is numerical .
URL might have limitation to contain a specific set of characters, and if your ExtractID includes characters that are not allowed in a URL, you might need to encode them. Could you please try using header as
and see if it works.
Please let us know how it goes. Thankyou