Okay, I’ll explain in detail what I see.
Test 1 shows us your SD and your disk. Your SD is all the partitions shown (They are correct) and your disk ( /dev/sda1 ) shows us that it has a capacity of 1.9Tb and that it is 100% occupied. Full, it can’t store any more. For that reason, the rest of the tests.
Test 2 shows us that everything is fine including the folder /home/umbrel/umbrel/app-data where each app is located and where everything related to each app is stored. In your case and as an example, there you have the bitcoin-core folder and the blockchain stored there. The data is correct and consistent. The folder /home/umbrel/umbrel/app-data weighs 802Gb which is correct at this time.
Test 3 confirms that the previous folder has the corresponding storage and is correct: 802Gb.
Test 4 confirms all of the above. Corresponding storage is correct: 802Gb.
In conclusion, your system is seeing and storing what it should correctly.
With the information available, everything leads me to think that the problem is with your disk. I remember you mentioned the following:
I copied the blockchain from the old ssd to the new one using a guide from the forum and everything worked fine with the new ssd showing the correct occupied space for several weeks.
I think that, maybe you did not copy the blockchain correctly and/or the system has duplicated the content on your disk making it full and without being able to detect it.
Well, let’s resolve that doubt. Let’s go directly and strictly to your disk and confirm. Via SSH execute the following commands and paste the results.
Test A:
sudo du -h --max-depth=1 /mnt/data
Test B:
sudo du -h --max-depth=1 /mnt
I’ll tell you right away that if the results are correct and match the results of the previous tests, then all that remains is to think that your disk is a fake disk or is damaged.
But, well… let’s see what the test shows…