It is hard to know what you are doing wrong without seeing the ad or your website but I could make two guiesses here:
First, as a new poster all your posts are moderated. this includes the post you just made here, and any ads you try to post. Moderation means there is a delay before your posts appear on the board. So, If you are expecting them to appear instantly, that may be the issue. Just give it some time. Now if you did know about moderation and if they still haven't posted after a few hours (Usually moderated posts only take minutes, but sometimes it takes a lot longer), then there is another issue preventing your ads from posting.
My second guess is that you don't have the TER logo/link on the first or main page of your website. This is a TER requirement in order for you to post your website link. If that is the case, then try to get the link on your website so you are able to link the website, but in the meantime, if you have an ad somewhere else, you can link your TER ad to another internet ad on an ad mall such as EROS, Slixa, or even backpage, or a profile on a verification site such as p411. You can't link to an ad on another review site though.
Click on your 'MyTER' link at the top of the page, then go to 'My message boards.' There should actually be a reason posted there as to why your ad was not approved (If in moderation, it will say 'new', otherwise it will either say 'active' or 'not allowed') There will be a reason there. Sometimes, the reason listed may not make sense to you. If that is the case, you can use the contact us busson and ask admin why the post was not allowed.
I have posted a link below to the provider ad posting guidelines. Since you mentioned that you followed everything to the t, you may have already read these. If not, be sure to check them out before trying to post another ad. These are found in the self help center which is found at the top of the page near the red and white life preserver. I recommend you actually read the whole self help center as there is some good info on the hobby and TER.
Welcome and Good Luck
