Led Snowflake Fuses On Christmas Light String Blows Immediately. Any Reason Besides Too Many Strings Together?

Fuses on Christmas light string blows immediately. Any reason besides too many strings together? - led snowflake

I decorated with LED lights snowflake plug fuse blows immediately when both know that if I pull too many strings, linked the first chain, is responsible for all the current needed for this responsible and strings attached below, which is usually the reason, the fuse blows. So I tried it but still come together and the fuse immediately. (I can see lightning and hear the pop)
I saw the channel very closely and saw no need for exposed cables or something. All ideas what could be wrong?