I saw your other post about replacing your NExT. I have to say that it is extremely unlikely that the LF T5577 chip in your NExT is “faulty”. I’ve never heard of that happening before. The problem is almost certainly related to the configuration of the tag or the read range. RFID systems are a finicky mistress, and you need to get used to it before you can say anything for sure.
There are definitely more troubleshooting steps you can do before you take the drastic step of replacing the implant. Especially considering you don’t have access to a professional installer. There’s even a chance that if you replace it the same thing will happen again, because there are other parts of the system at fault.
You’re going to need to give us more information if you want help.