Can I ask seller questions in pending?

[Yoon Seokwoo]

I am in the process of buying a house for my primary residence.

My offer got accepted and we finished inspection and all the negotiation. I am waiting for my loan approval and the house is under pending.

Later I noticed that there was no furnice filter in that house so I asked my buyer'agent to ask seller what size and type of filter they used for their furnace. My buyer's agent said it is not appropriate to ask this kind of questions at this stage, which I didn't understand why.

Is it common practice in real estate transaction that this kind of info is not communicated between buyer and seller side at pending?

Thanks.