Formula produces Error

All,
I have the following array formula:

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However when I try and make it the following formula:

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So basically I added the following line:
,IF(Data!$H$2:$H$955>=B1,IF(Data!$I$2:$I$955<=C1

B1 and C1 are dates so I'm just comparing if it's in between these dates. Any ideas why my second formula produces an error?

Thanks in advance.