You can use EasUS Partition master for the job.
Another will would be to delete the second partition adn extend the first partition form Windows' inbuilt disk management utility. But I'll recommend using EasUS Partition Master.
I'm not sure if that drive is shown in Windows partition manager, because it was formatted in some other file system
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I recovered that partition using EaseUS, but I wasn't able to merge it with the partition that I wanted. I had to merge it with Lenovo's backup partition