Correct spelling, explanation: when we want to create a past participle or past simple of the verb submit, we must add the suffix -ed and double the consonant. It’s worth mentioning that it’s not always the case when it comes to irregular verbs: we need to double the last (and stressed as well) consonant in a basic word if there’s a single vowel before it. Always remember that rule and you won’t make that common mistake. Therefore, the only correct spelling is submitted, not submited.

Definition of submitted:
verb (past simple, past participle), to suggest or say something
When I was on a trip to Italy, I submitted that we should see Venice.
My mother submitted that my CV should be improved.

Phrasal verbs with submitted:
Some most commonly used phrasal verbs include: submit for.
If you wrote your own novel, it can be submitted for publication.

Incorrect spelling, explanation: it’s not always enough to just add a specific suffix to the end of a verb in order to create a past simple/past participle form. Sometimes we also have to double the last, stressed consonant – when there is a single vowel before it. That’s why you can’t spell submitted as submited – it lacks the double -t letter. One must remember that it consists of three parts: submit + t + ed, so it’s not right to omit any of them. Submitted is the only correct version of this word.