I cant sleep well last night

I cant sleep well last night
Because there is an important event at the company next month
So I need to prepare for company event

But There's a problem
Because the employee who was in charge of the important work quik last month due to personal reasons

I think I'll be very busy this month

I couldn't sleep well last night because there is going to be an important event at the company next month, so I need to prepare for the company's event.

But there's a problem, the employee who was in charge of the important work quitted last month due to personal reasons.

I think I'll be very busy this month.

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Hi, Stellar!

You have to be more conscious on the usage of proper verb tenses in your sentences to improve your writing skills.