Time Machine backup not completing/backup size increases

I have been attempting to back up the computer to my My Cloud Home 8TB drive ever since I have purchased it last month. Time machine does not appear to be finishing the back up and the backup size keeps growing. There have been times I have had to skip backing up when turning off the computer.

I have had the computer on from approx 11 pm Monday night to approximately 9pm Tuesday night and still had the same problem. At 8.02am Tuesday, it was backing up from 202.25 GB of 222.47 GB At 5.36pm that day, it was backing up from 1.23TB of 1.35TB. Then at 8.10 pm it went back down to backing up from 48.60 GB to 53.46GB.

After I verified back ups, Time Machine read Oldest Backup: None, Latest Backup: None. This was at 10.22pm Tuesday.

This morning, I had received an email from My Cloud Team stating, “Your device has 1955 GB remaining”.

I am running Mac OS High Sierra, Version 10.13.6.

Any tips on how to resolve the above issue would be greatly appreciate.