Shadowfax - Packages not being delivered

I am writing to file a formal complaint against Shadowfax for repeated service failures and unprofessional conduct by their delivery personnel.
This is not an isolated incident. I have faced the same issue multiple times, and despite raising complaints repeatedly, there has been no resolution. The same delivery person, Mr. Sadik Sayyed (***** *****), continues to be assigned to my orders.
In the latest incident, the delivery person has blocked my contact number, making it impossible for me to coordinate or receive my delivery. This is highly unprofessional and unacceptable behavior. Additionally, his manner of communication has been consistently disrespectful.
Due to these repeated failures:
My orders are not being delivered
There is no accountability or resolution from the company
The same delivery personnel is reassigned despite complaints
Customer service has been ineffective
This reflects a serious lapse in service standards and customer handling.
I request immediate and strict action against the concerned delivery person and a permanent resolution to prevent such incidents in the future. Failing which, I will be compelled to escalate this matter further through appropriate consumer grievance channels and legal means.
I expect a prompt response and resolution.