Quick answer
It is almost always your role. A message that says your role does not have permission names the capability the action needs and tells you to ask a partner. The screens hide what your role cannot do, so a missing button is usually the same thing rather than a fault.
What each role can do
Assistant. Setting up: create clients and jobs, enter the engagement details, upload records, and remove a file dropped in the wrong slot. Not the accounting work, so no running steps and no recording decisions. The policy, memory and audit sections are not available and say so.
Junior. Everything an assistant can do, plus the accounting work: running steps, recording decisions, posting adjustments and recording call notes. Not archiving a job.
Senior. All of the above, plus archiving a job, and the answers that step past a warning.
Partner. All of the above, plus firm settings: inviting users, changing roles, the firm's house wording and learning.
The answers reserved to a senior or partner
Some options are a deliberate step past something AllDone raised: accepting a difference with a reason, continuing without a piece of evidence, proceeding when the records score is below what was agreed, dismissing an outstanding record. A junior still sees the option and the explanation; the control is replaced by a line saying who can record it. The rule is enforced behind the screen too, so it cannot be worked round.
Getting your role changed
Ask a partner. Settings, Users lists everyone in the firm with their role. You can only assign a role up to your own level, and the firm's last partner cannot be moved down, so there is always somebody who can manage settings.
Two other reasons a control can be missing
Your account has been disabled, in which case nothing works rather than one button.
The action belongs to the job's state rather than to you. A step that has not reached its turn yet, or a document that is produced later, is described by the screen in terms of when it will appear.
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