This seems to be a US thing at least at the moment. Here is Switzerland the government specifically says if you have had a positive Corona test you should not

This seems to be a US thing at least at the moment. Here is Switzerland the government specifically says if you have had a positive Corona test you should not vaccinate for at least 6 month and if you do after that only 1 shot not 2. Then again we had a vaccine shortage so that may also have something to do with it.