"Please open your store now."
But it's おみせ, so "Please open the cash register at your honorable store". These thieves are strangely polite.
Question: There is not a は between 今 ＆ あ, why? Reported my answer: 今はあなたの店を開けてください。
That's more like "So, on the topic of 'now,' please (have that be when you) open the store." The topic isn't "now."
I'm not good enough to explain it in detail to you but it looks to me like you structured that incorrectly.
Lol trying to imagine a japanese person banging on a shop window saying this
For those who are confused, imagine a police officer having just explained that there could be evidence of a crime in a store after they have shut for the evening. Then he says, "Please open the store now."