not able connect Source tree and Gitlab

[Saju Sam]

When I am trying to connect source tree with GitLab(SSh) getting the following issue

Command: git -c diff.mnemonicprefix=false -c core.quotepath=false --no-optional-locks ls-remote git@gitlab.XXXXXcust.org:xyzprd/XXXXXX.git

Output:
Error: The server's host key is not cached. You have no guarantee
that the server is the computer you think it is.
The server's ssh-ed25519 key fingerprint is:
ssh-ed25519 255 SHA256:ficiPh7ZtDIfa42M92lSX/Vp0Y2ifvqonjJ1BANXeIk
If you trust this host, enter "y" to add the key to
PuTTY's cache and carry on connecting.
If you want to carry on connecting just once, without
adding the key to the cache, enter "n".
If you do not trust this host, press Return to abandon the
connection.
Store key in cache? (y/n, Return cancels connection, i for more info)

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Link Followed

https://www.awordfromnet.com/access-gitlab-via-sourcetree-updated/?unapproved=1488&moderation-hash=3df180e29bf118f7cd65d3701f12ac20#comment-1488.

Any help appreciated

Thanks A Lot