I am not sure if it's fair for me to blacklist them now when previously they had done a great job with my deliveries

I am not sure if it's fair for me to blacklist them now when previously they had done a great job with my deliveries. It's just that it's frustrating not getting any feedback from the company that's supposed to be rendering services especially under a Big International Company like SheIn. I haven't had any feedback about my order since the 10th of November and when I called iMile an agent told me that my package is stuck overseas which I find it very surprising where as when I check my SheIn App it shows that my package has been shipped already and it's showing imile as the logistic company that should be tracking it. It's totally unfair that we have to wait this long for stuff that we've paid for and paid customs for. SheIn should be alerted about this issue.