I have 1 drive locked with Bitlocker but deleted this partition unintentionally.
please help me .. what must i do?

if you have only deleted the partition and you know the correct password, it is possible to recover the partition.

can you tell us the original and current partition structure ?

Testdisk or DMDE will help in this case.

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Data Recovery Pakistan

Well,
Last time i had quite some issues with such kinda problem in my case the partition was formatted and overwritten with 32 gb data .I recovered this [ not using any tool mention in this post ] . I will not share this solution

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Regards
Amarbir S Dhillon , Chandigarh Data Recovery Labs [India]
Logical,Semi Physical And Physical Data Recovery
Website-> http://www.chandigarhdatarecovery.com