I have a simple iframe:

<iframe name="eurosp" src="" width="100%" height="470px" marginheight="0" marginwidth="0" scrolling="no" frameborder="0" allow="fullscreen" allow="encrypted-media"></iframe>

and a bunch of links that i want to load on click inside the iframe:

<p><a class="button-30" target="eurosp" href="link1">[ link 1 ]</a></p>
<p><a class="button-30" target="eurosp" href="link2">[ link 2 ]</a></p>
<p><a class="button-30" target="eurosp" href="link3">[ link 3 ]</a></p>p

When i click the first time on link 1 or link 2 or link 3 it opens properly inside the iframe. But after that, when i want to change, for example from link 1 (already open in iframe) to link 2 (so i want link 2 to open inside iframe replacing link 1) does not work.

What am i doing wrong? And if there is no simple explanation (which i would prefer) is there any simple script that empties src before i insert the new link?