Xfinity Trade In Device Credits not being applied as the Old Device as per them is Still in Transit

Recently I moved to Xfinity from TMobile when they have Iphone 16 Pro trade in offers are going on Oct 9th 2024. I have created a new account and traded 2 IPhone 13 Pros for 2 Iphone 16 pro Max. I have got the 2 new devices timely and was able to activate my 2 devices. I have sent my old devices immediately after taking all the care. As per the USPS my devices have already reached on Oct 23 and other Oct 28 in timely manner before the deadline which Xfinity has asked me to do so. Surprisingly for 2nd device which reached them on Oct 28th, I have received confirmation that trade in accepted and adjusted my bill for that line. But for the device which reached them on Oct 23, they have been saying that device is still in transit to Xfinity from Assurant which is not of my concern. Every time I call them, they say everything is fine device is reached, device is graded as good and credits will be applied immediately like that. They have been repeating the same story every time I call (more than 5 times)and till date they haven't provided any confirmation. Seeing the similar issues happening with others in this community forum, I am more worried what is happening with my device which I sent and to the credits which i should be getting.

Any inputs will be appreciated,  considering the very poor service from Xfinity.