Conditional VLook

Hi everyone,

Currently I am creating an automated data base. I'm seeking for your help and expertise about conditional vlookup, the formula is below. Can you please detect what is the problem in the formula? the result is always at "0" because iferror is added, however the result is blank if iferror is removed.

=IFERROR(IF(VLOOKUP(D15,'EM Feedbacks'!A3:A58,1,0)='BA_2021 MAR'!D15,IFS('EM Feedbacks'!C3=Validation!$F$3,Validation!$D$3,'EM Feedbacks'!C3=Validation!$F$4,Validation!$D$11,'EM Feedbacks'!C3=Validation!$F$5,Validation!$D$12)," "),0)

Please help me how to fix this? Thaaanks!

Note: EM Feedbacks, BA_2021, Validation are sheet names.

Thank you in advance everyone!~