Inspiron 15 3501, Alert TPM device is not detected

Hello,

At each boot of my Inspiron 15 3501 (bought it less than 1 month), I get the error message: "Alert! TPM device is not detected". Supposing that the TPM chip is no longer effective on the motherboard is hard to conceive because the laptop is completely new. Possible tracks/guesses on the causes of this error can be:
- BIOS updates (suggested by DELL).
- The battery reached twice a critical level.

To the best I know, Inspiron 15 3501 does not have TPM module but contains Intel PTT feature which somehow replaces the role of TPM. But I can see any of them when I enter BIOS setup (with F2) and look for TPM/PTT under the security tab. Naturally, TPM 2.0 is not detectable by Windows 10 either (under device manager, I get the error message: "Compatible TPM cannot be found").

When the error started to show up, the BitLocker software asked me to enter a recovery key. This clearly means that before the error the module TPM/PTT was working correctly by providing a key to BitLocker for unlocking the internal hard drive.

I applied many solutions I could find on internet, including the ones I could find in official DELL documentation. However, none of them was effective. Here are the solutions I applied:

1- Downgrade BIOS from the latest version (1.18) to previous versions (1.17 and 1.16). This didn't solve the issue.
2- Reset BIOS to factory/defaults settings. This didn't solve the issue.
3- Shut down the PC, then held down the keystrokes Ctrl + Esc while plugging in the AC power. Well, after applying this solution, when I reboot and click directly on F2, I can see again PTT feature appearing. But just exiting the BIOS and restarting, the former error comes up again and the PTT feature disappears from BIOS settings again.
4- Shut down the PC, then maintaining the power bottom held down for 60 seconds before powering up and plugging in again the AC power. The results of this solution are the same of solution 3 just above.

Please, could you give me more feedback/explanations on the causes of this error message, and more importantly the solutions for remediating definitely?

Thanks in advance for your discussion and propositions.