Yanwen is considered to be a legit shipping provider. The only problem is that the delivery of the packages usually takes longer to arrive to you. To know whether or not you have a legit tracking number, you can enter the Yanwen tracking number on the homepage of Ship24.
If there are tracking results that show up, then that means that your Yanwen parcel is on its way to you. If there aren't any tracking updates, double-check your tracking numbers and if there's still nothing, contact Yanwen customer service to resolve this issue.