Have you ever opened a compressor and found that the oil has become “semi solid”..a bit like grease! The compressor probably failed because they require oil to lubricate them!! Gummy oil all is always associated with pollutants of some kind. These may range from over the counter additives to improve and or seal the system to refrigerant that is not compatible with the oil in the compressor. It is never a good idea to add chemicals to your system that promise quick solutions. In fact you should not add any chemicals that are not endorsed by the vehicle manufacturer. The least costly fix is to take your vehicle to a professional shop. Check the blogs on the internet if you have any doubt!!
Ensure that you use refrigerant and oils from a source that can guarantee purity back to a national standard. There are large quantities of weird mixtures about that are being sold by many large WD’s. If the label does not quote a national standard, then DO NOT USE IT.