SQL Server Error: Cannot insert explicit value for identity column in table 'Polls' when IDENTITY_INSERT is set to OFF.

I am creating the survey poll and down the road I am facing the errors. Please help me to get thru this survey poll. Thank you.

When I click the UPDATE Button I get this error.

Cannot insert explicit value for identity column in table 'Polls' when IDENTITY_INSERT is set to OFF.

Here is the table structure:

PK_Option - Primary Key

PK_PollId - Foreign Key

Stored Procedures used here:

 ALTER PROCEDURE dbo.NewPoll
       (
       @v_Question         VARCHAR(200)
       )
AS
 
--     FINDING THE ID OF THE NEW QUESTION

DECLARE @i_NextQuestionID  INT
 
--     INITIALISIG QUESTION ID
       SET @i_NextQuestionID = 1
 
--     IF THERE ARE MORE POLLS, THEN SET THE QUESTION ID TO MAX ID + 1
       IF ((SELECT COUNT(*) FROM Polls) > 0)
       BEGIN
             SET @i_NextQuestionID = (SELECT MAX(PK_PollId) + 1 FROM Polls)
       END
 
--     FIRST, SET THE OTHER QUESTIONS AS INAVTIVE
       UPDATE Polls
       SET           Active = 0
 
--     INSERT THE NEW QUESTION IN THE TABLE POLLS
       INSERT INTO Polls
                    (PK_PollId, Question, Active)
       VALUES (@i_NextQuestionID, @v_Question, 1)
 
       RETURN