TWRP OnePlus 5T not asking for encryption password

I want to flash the new Update for the OnePlus 5T but TWRP is not asking for a decryption password as usual and hence cannot mount the data partition.

It's possible that this is not working since the last update (OnePlus 5T OxygenOS 4.7.6).

Is there a way to force the decryption, for instance by some command in the TWRP terminal? Or is there a way to reset this?

In the Android settings, the Encryption Option is not changeable, it just says "Encrypted".

UPDATE: Obviously OTA Updates are possible now, I don't know how. Till now, with custom recovery and/or root this was an issue and not possible so you had to download the Update manually and install it through TWRP or other recovery.

During OTA Update, the recovery was overwritten with the original from Oneplus.

The option for Smartphone encryption in the settings remains unchangeable, so I believe I could not change the code if I wanted to.

Answer

From the TWRP terminal enter the command twrp decrypt

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