Duplicate key value violates unique constraint when trying to insert

I'm using drizzle-orm to work on my Postgresql database...

I have this simple table:

export const ExperimentData = pgTable('experiment_data', {
  id: bigserial('id', { mode: 'number' }).primaryKey(),
  timestamp: bigint('timestamp', { mode: 'number' }),
  websiteId: bigint('website_id', { mode: 'number' }),
  experimentId: bigint('experiment_id', { mode: 'number' }),
  variantId: bigint('variant_id', { mode: 'number' }),
  event: varchar('event', { mode: 'string', length: 255 }),
  data: json('data'),
});

and I have a script that reads data from Redis and writes to this table:

await statisticsdb.insert(ExperimentData).values({ timestamp, websiteId, experimentId, variantId, event, data });

this script runs is supposed to run every hour, triggered by a cronjob and now it doesn't run because I get the error

PostgresError: duplicate key value violates unique constraint "experiment_data_pkey"
 code: "23505"

      at ErrorResponse (/home/ubuntu/production/pertento/node_modules/postgres/src/connection.js:792:23)
      at handle (/home/ubuntu/production/pertento/node_modules/postgres/src/connection.js:811:5)
      at data (/home/ubuntu/production/pertento/node_modules/postgres/src/connection.js:562:3)
      at emit (native:1:1)
      at addChunk (native:1:1)
      at readableAddChunk (native:1:1)
      at data (native:1:1)

this error is caused on the first insertion try.

I haven't done anything, haven't changed the schema or the data in the database
as you can see, the only primary key I have in the table is the id field
am not trying to force the id

I don't know exactly what to do here. Also, don't want to mess up the data in Postgres nor in Redis.

Update

After running

select * from public.experiment_data_id_seq;

I get the value: 253020

looking to the database, the latest ID is 1171578 which is waaaay off.

How can I fix this? Can I just update this value in the database directly?

Solution

Find who or what changed the sequence and make sure they/it are prevented from doing that again.
Pick a number that is max(id) + 100 or so and do:

BEGIN;

ALTER SEQUENCE  public.experiment_data_id_seq RESTART <above_number>;

ROLLBACK or COMMIT above depending on success or failure.