celestion a2 tweeter blown or not

I have a Celestion A2 floor standing speakers, both tweeters are now silent after I hooked them up to a Karaoke system and started to sing ;^(. I took them out of the enclosure and looked inside particularly at the diaphragm, they both look intact, clean and undamaged. What can be wrong with my speakers ?

Any idea for how to fix it ? Looking for original parts might be a dead-end since these models have been discontinued for years.

Both the Midrange and Woofer still sound very good, seems not being affected. I don't know if anything in the cross-over might cause the tweeter to not being able to function.