bbs.spamgourmet.com

I have been using SG for years and have over a hundred disposble addresses. Basically I set up a new disposable address for each company / supplier I deal with.
I signed up for a software delivery and relationship. I did not receive any replies from the supplier. I the checked SG and my spam in case the emails had been 'deleted'; nothing.
I sent myself an email at the disposable address: it never arrived, the disposable address is not on SG.
The disposable addresses that disapear are 'legacc.brabason@dfgh.net' and 'legacc.brabason@xoxy.net'. 'leg' is unique to the company, 'acc' is one of my watch words, 'brabason' is my web alias.
I have many address with this format but this one just does not work. 'legswp.brabason@dfgh.net' does work, almost as if the 'acc' watch word was failing on this one.
Any ideas?

I think some companies have something on their outbound email server that stops it from delivering it to SpamGourmet. Not many companies. And I am not sure what.

No company involved. I send myself an email at this address. No dispoable address created. Only SG and my ISP involved. Never any problems with ISP. That is why I think it is SG.