prsent simple with tonight

[Allthewayanime]

Could someone explain to me why the present simple is used with 'tonight'(in this context, shouldn't it be the present progressive)

hold your hands up, I miss you, i miss you tonight
hold your hands up, I'll find you when i look inside

[Dozy]

"I miss you tonight" and "I'm missing you tonight" are both possible. There is not much difference in meaning.

You should try to get into the habit of writing "I" not "i", and starting sentences with capital letters. Many learners seem to think such things are unimportant -- or seem to have never been taught them at all -- but they really make a huge difference to the quality of your writing.