A procedure for identification of the chemicals substance type based on their names was recently implemented in QSAR Toolbox. The procedure searches in the chemicals names for presence of some predefined key words. In case such key word is identified, then the substance is defined as "polymer" or "UVCB".
Profiling results for the chemicals with substance type "Polymer" or "UVCB" are not provided.
However, if you still want to profile such chemicals (as in your case), you can copy the SMILES, paste it in a notepad and then save it. Once you have the saved file, go to Toolbox and load the file. Select "No" in order to load the structure as it is. In this way, the structure will be loaded on the data matrix without ID information (CAs,Name) and hence, it will be not identified as polymer.
Thank you Darina for the great explanation and the workaround!