A press release by the Spanish government and a thread of tweets by the Chinese Embassy in Spain refutes the claim.
The Chinese Embassy in Spain issued a clarification regarding the test kits in a thread of tweets stating that donations made by the Chinese government and companies such as Alibaba didn't include products supplied by Shenzhen Bioeasy Biotechnology. The Chinese Ministry of Commerce has offered a list of a classified supplier to Spain, in which Shenzhen Bioeasy Biotechnology was not included, and it had not given the official license from the National Medical Products Administration of China to sell its products.
The health branch of the Spanish government also responded saying that the government did not purchase those tests from China. They bought it from a national supplier called Bioeasy kits, which is certified by the European Union, which can be legally sold in Spain.
According to Formosa TV English News coverage, the Czech Republic's Deputy Health Minister Roman Prymula had also stated that the 80 per cent error rate was not true, adding that there had been only 20 to 30 per cent error rate with the test kits.
The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19 including symptoms, prevention and available treatment, please refer to the World Health Organisation or your national healthcare authority.