Hi @Anonymous ,
It is helpful to post some field, list and control names, but a Lookup column needs some further "treatment" to filter on (incidentally they are completely unnecessary in Power Apps and will only cause you unwanted difficulties on many levels. The syntax would be
Filter(
AddColumns(
ListName,
"WhateverName",
LookupField.Value
),
WhateverName = YourDropdown.Selected.xxxx
)
where xxxx is the valid output of the dropdown(Value/Result/FieldName). Note that this is not Delegable - it will only work on list numbers up to your (500-2,000) Delegation limit.
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