confusing on conditional reasoning

1.Bank deposits are credited on the date of the transaction only when they are made before 3 P.M. Alicia knows that the bank deposit was made before 3P.M.So, Alica knows that the bank deposit was credited on the date of the transaction.

1)Bank deposits are credited on the date of the transaction only when they are made before 3 P.M.

    COT=Credited on the date of the transaction 

COT(sufficient)--------3PM(Necessary)

I feel good with this result.

2)Alicia knows that the bank deposit was made before 3P.M.So, Alica knows that the bank deposit was credited on the date of the transaction.

My question is that how we can get the following out from the above sentence?

3PM(sufficient)--------COT(Necessary)

I think you didn't confuse the conditioning in this question, the only thing is maybe you didn't read the question stem carefully. If it's the one on one of the actual tests, I think it is a false argument based on which you are asked to find a similar flawed argument~ Hope it helps~ Please tell me if I am wrong~

I think you are right in some way.However, my issue is that i got confused with the following sentence.

"Alicia knows that the bank deposit was made before 3P.M.So, Alica knows that the bank deposit was credited on the date of the transaction."

I think( just focus on this sentence and forget the others):

1)."Alicia knows that the bank deposit was made before 3PM" occurs first.

2)."Alica knows that the bank deposit was credited on the date of the transaction" occurs second.

How can we get that 3PM is the sufficient and COT is the necessary?

Finally, i figured it out.

 "If the sufficient condition occurs, then it can be concluded that necessary condition has occured."