Huggingface not saving model checkpoint

I am trying to train T5 model. This is how my training arguments look like:

args = Seq2SeqTrainingArguments(
model_dir,
evaluation_strategy="steps",
eval_steps=100,
logging_strategy="steps",
logging_steps=100,
save_strategy="steps",
save_steps=200,
learning_rate=4e-5,
per_device_train_batch_size=batch_size,
per_device_eval_batch_size=batch_size,
weight_decay=0.01,
save_total_limit=3,
num_train_epochs=10,
predict_with_generate=True,
fp16=True,
load_best_model_at_end=True,
metric_for_best_model="rouge1",
report_to="tensorboard"
)

My model trained for 7600 steps. But the last model saved was for checkpoint 1800:

[trainer screenshot](https://i.stack.imgur.com/MBoFu.png)

Why is this so?

fp16 huggingface languagetechnology look saving tensorboard training true