How to create the new variable flag based on Flag Indicator

[Spintu]

Having data is my actual data. I am trying to create as per SUBID, if TESTCD = ' DOSE1T' and TPT value is "SBDOSE" then date value should be SB_DATE. Similarly, for DBDOSE.

I am having issues with if I select TESTCD = ' DOSE1T' then TPT value is blank. 

Having data:

SUBID	TESTCD	DATE	TPT
101	DOSE1T	19-Feb-22
101	NAUP
101	PHTP		SBDOSE
101	DOSE1T	25-Feb-22
101	NAUP
101	PHTP		DBDOSE
102	DOSE1T	26-Feb-22
102	NAUP
102	PHTP		SBDOSE

Expecting output:

SUBID	TESTCD	DATE	TPT	SB_DATE	DB_DATE
101	DOSE1T	19-Feb-22		19-Feb-22
101	NAUP			19-Feb-22
101	PHTP		SBDOSE	19-Feb-22
101	DOSE1T	25-Feb-22			25-Feb-22
101	NAUP				25-Feb-22
101	PHTP		DBDOSE		25-Feb-22
102	DOSE1T	26-Feb-22		26-Feb-22
102	NAUP			26-Feb-22
102	PHTP		SBDOSE	26-Feb-22

[PaigeMiller]

Show us the full code you are using, and if there are errors in the LOG, then show us the full LOG as well. Please provide data as working SAS data step code (instructions) and not in any other format.