Can anyone clear this lock, so that I can answer questions again?
The answer is unfortunately no, as it is an automated block.
Stack Exchange has automatic filters in place to ban answers from accounts that have posted numerous low-quality answers in the past. These filters help keep the quality of our sites high.
...
How can I get out of an answer ban?
The ban will be lifted automatically by the system when it determines
that your positive contributions outweigh those answers which were
poorly received.
Stack Exchange cannot lift answer bans by request.
The only way to end a posting block is to positively contribute to the
site; automatic bans never expire or "time out". Begin by fixing your
existing answers; do not just post the same answer again or delete all
of your existing answers. All answers are expected to be useful to
future visitors, in addition to the original asker, so keep the
following tips in mind when improving your answers:
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Source Why are answers no longer being accepted from my account? - Help Center - Super User
So far, on SuperUser, you have posted 3 (currently deleted) answers with a total score of -1.
I've undeleted the only answer that I think can be improved (https://superuser.com/a/1107906/337631).
Please read How do I write a good answer?, and try and improve yours (hint: It needs to be a standalone answer that completely answers the question).
Notes:
- You are not currently blocked from asking questions on SuperUser.
- Any issues you have with your account on ServerFault should be raised on their meta.