Leaving the U.S

Hello everyone,
I was working in the United States on a H1B visa for a few years. When I left the company I worked for and the States to go to a third country should I have informed IRS about it? I did not file any tax papers after I left the country. I was paid a salary for 4months I was in the U.S after I filed my last tax form and I didnt receive my W2 for that period since I wasn't in the country when they sent it out.
Will I get into trouble if I return to US on a visit?
Does anyone have any ideas?
Thank you so much!

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