I am trying to link my USCF ID 15453455 to my profile to play tournemant today.
Linked it in USCF website few weeks ago and still says I cannot play tournaments as it is not linked.
Who can help? What is the process as there are other kids from my club try to do the same thing and have issues.
Appreciate any help

My experience is that the linkage is done by the tournament director along with the ICC support team. I didn’t try to do this in USCF site. For example, CCA has its own registration page, https://register.chessclub.com/cca, which will ask you to provide your USCF ID in the second step. Once you register for a tournament, I typically get an automatic email to ask you to send your USCF ID and ICC username to the TD so that they can confirm the linkage or setup the linkage for you.
The ICC support contact can also help on this issue. They can confirm if the linkage is established in their system.

I am having the same problem.  My uscf id is 12669397 and i confirmed this on my chess life and uscf web site but it keeps saying handle does not match uscf id

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