Bitlocker drive encryption

Question

I encrypted my D drive few months ago with bitlocker. My Windows OS is in C drive. After 2 months, i opened my laptop and tried to access data of my D (encrypted) drive by using password but bitlocker is not accepting password. I don't have recovery key (neither in my ms account nor in my laptop etc). I am 200 percent sure that password is correct but bitlocker is not accepting it. I have tried all possible tricks like using cmd commands, using different data recovery and disk decrypting softwares but in every situation, only one message appears that the password is incorrect. In This Pc windows, i can see the folders of my encrypted drive D in left hand side list but i can't open it. I don't know if i have updated my windows 10 few months ago before shutting down my pc or not. But this time windows prompted me to install windows 10 20H2 version, and i installed it.
But it doesn't help in any way.
I have done secure boot, windows reset etc but zero result.
I doubt that i encrypted my D drive in older version of windows 10 and now installing new updates of windows 10 corrupted the meta data of encrypted disk.
I have gone through many online platforms for suggestions and help, i tried many methods and i am not sure if the disk is corrupted or new updates of windows rendered this.
Please help me out as i have important data on this D drive and i don't want to format it.