I don't think it is possible to get sellers to understand Sendle, Couriers Please and Fastway are garbage when it comes to deliveries. They book the courier service, the item is picked up efficiently and they think the company is brilliant. Sigh.
I last had this issue with a seller who insisted on using Sendle 'as she had no end of issues with Aust Post'. So my item got sent using Sendle....who passed it on to Couriers Please in my location......and then nothing happened. I contacted the courier company and the seller. The couriers (after some prodding) agreed to look for the parcel (which was God knows where at their depot for weeks). The seller told me 'she had never had any trouble with Sendle before'.....and it turns out she also had no idea whoever picked up the parcel was not necessarily the couriers that deliver it.
Finally the parcel was located and was (slowly) on its way to me. In the meantime the seller had seen the tracking and also contacted the company. They told her (and I quote!!) 'The parcel was handed over to Aust Post for delivery'. Of course it wasn't!! Sendle and AP are in direct competition and have made complaints against each other.
After more conversations with the Seller after my purchase finally arrived, she told me AP was 'terrible' because of parcels lost once they left Oz and arrived overseas. I pointed out that was hardly AP's fault but likely the postal/customs/whatever services in the respective countries. I also told her my parcel had a Couriers Please label on it (big surprise.....not) so the company lied to her that AP were at fault for its slow delivery.
I can only hope her eyes were opened to the true state of certain couriers in Oz. One company at least certainly helped my opinion of them by deliberately lying to the seller that they had given the parcel to Aust Post. It seems on many levels they are not the smartest knives in the block.
Oh, and a recent purchase (not eBay) was sent by Couriers Please - a big bulky padded bag of 4 boxed (but thankfully not breakable) items which the delivery person somehow managed to fold over and cram into my letterbox so the letterbox lid wouldn't close properly. It was only a short walk to my safe drop spot from my letterbox but apparently he couldn't be bothered. Two boxes were crushed but the contents were OK thank goodness. Couriers Please lately have been worse than Fastway....and that's saying something.
All any buyer can do is notify the seller and hope they finally see the light, and avoid these dodgy companies. At the very least Sellers should state they use couriers instead of Aust Post. 'Standard Post' is NOT couriers!
