The seller is allowed to solicit backup offers while there are outstanding contingencies. Pending Sale means that the property is under contract for sale, however there may be language in the contract that allows the buyer to cancel the contract. The seller is allowed to solicit (but not accept) backup offers in case the buyer cancels the contract.
My esteemed colleague Joan provided a very real life description as to why the property is still showing for sale. If you'd like you can email me the address your referring too and I can check the status on the MLS.
This seems to happen a lot as the market is crazy right now. Some agents are inundated with multiple offers. I have seen 35 offers come in on one listing recently. Possibly the agent just has not had time to mark it pending. Or perhaps, different websites such as Realtor.com are not always current. The MLS (typically) is the most current unless the agent like I mentioned, just has not had the time to mark it pending.
If I can be of any assistance, let me know. I know the market is tough right now due to lack of inventory. So, if you are already working with an agent, keep that in mind. Don't give up!
Joan Patterson, B.A., G.R.I., Realtor, License #01431647
Keller Williams Realty