This is my first time participating in a kaggle competition and I'm having trouble submitting my result table. I made my model using gbm and made a prediction table like below. the submission file has 2 column named 'fullVisitorId' and 'PredictedLogRevenue') as any other kaggle competition cases.

```
pred_oob = predict(object = model_gbm, newdata = te_df, type = 'response')

mysub = data.frame(fullVisitorId = test$fullVisitorId, Pred = pred_oob)
mysub = mysub %>%
  group_by(fullVisitorId) %>%
  summarise(Predicted = sum(Pred))

submission = read.csv('sample_submission.csv')
mysub = submission %>%
  left_join(mysub, by = 'fullVisitorId')

mysub$PredictedLogRevenue = NULL
names(mysub) = names(submission)

```

But when I try to submit the file, I got the 'fail' message saying ...

```
ERROR: The value '8.893887e+17' in the key column 'fullVisitorId' has already been defined (Line 549026, Column 1)
ERROR: The value '8.895317e+18' in the key column 'fullVisitorId' has already been defined (Line 549126, Column 1)
ERROR: The value '8.895317e+18' in the key column 'fullVisitorId' has already been defined (Line 549127, Column 1)

```

Not just 3 lines, but 8 more lines like this.
I have no idea what I did wrong. I also checked other kernels but couldn't find the answer. Please...help!!