UPS is facing an avalanche of criticism from angry customers who didn't receive their packages in time for Christmas.
Delivery delays are being blamed on poor weather and overloaded systems, but customers are lashing out on Twitter.
"Thanks @UPS for ruining xmas,” said one tweet, “Does a promised delivery date not mean anything to you?"
Another outraged customer tweeted: "I. Will. Never. Use. UPS. Again!"
One family even posted a YouTube video about gifts that didn't arrive in time for Christmas.
Some UPS drivers are firing back at the criticism, with one writing on the UPS Facebook page: "Got off at 1010 last night, 60hr weeks, I’m tired no reason 4 anyone to be mad Merry Christmas.'
Ups said in a statement: "We apologize that our customers did not receive their packages on Christmas. The volume of air packages in our system exceeded the capacity in our network."
Federal Express also experienced delays and says in a statement: "We're sorry that there could be delays and we're contacting affected customers who have shipments available for pickup."
CNBC consumer reporter Kelli Grant told INSIDE EDITION, "I think this is very embarrassing for these companies. Now, this is something where you see a lot of these stories out there, 'FedEx ruined my Christmas.' 'UPS ruined my Christmas.' They have to overcome that image and have to find a way to make amends to all of these costumers."
Meantime, at stores like Bloomingdale's in Manhattan, customers are using the day after Christmas to return gifts and take advantage of big sales. Many retailers are offering 40-60% off, some as much as a whopping 75-80% in an effort to offset disappointing sales this holiday season.
One customer said, "Taking advantage of the sales. Bloomingdale's right now, then going to Saks."
Another said, "There are a lot of sales going on today, can't miss those!"
Here's the bad news, in store retail sales are down 3.1% from last year. Foot traffic is down a staggering 21% from last year. Many customers have switched to shopping over the internet with online sales up nearly 14% from a year ago.
Grant said, "After some of the debacle of gifts that did not arrive on time, I think that may give consumers a pause in coming years and remember that they had that experience."
UPS says they brought in extra workers on Christmas day, but admit some packages may not arrive till the weekend. Meantime, Amazon is offering refunds to a number of angry customers.