"The till will not let me sell this item." Either the product has no stock recorded, or your role does not allow selling below stock. Receive the purchase that brought it in, or adjust stock with a reason.
"Stock says we have ten and the shelf has six." Something left without being recorded - breakage, staff use, theft, or a sale rung up against the wrong product. Adjust to the real figure with a reason recorded, then look at whether it keeps happening to the same lines.
"The drawer does not match at close." Check for a split payment recorded as a single method, a refund given in cash but recorded against card, or a sale voided after the money was taken. Count again before assuming the worst - the commonest cause is a miscount.
"A customer says they paid their khata." Look at the khata screen for that customer. If the payment is not there, it was never recorded. Record it with the correct date rather than today's, or the aging will be wrong.
"The by-employee report shows everything under one person." Staff are sharing a PIN. Give each person their own; the report cannot attribute what the system was never told.
"A promotion did not apply." Check the offer's dates and which products or categories it covers. An offer that has expired, or that was set on a category the product is not in, will not fire.
"Profit looks wrong." Usually expenses. Sales are recorded automatically because they go through the till; expenses only exist if somebody enters them. A profit figure with no expenses behind it is a revenue figure.
"I cannot see another branch's numbers." Your user is scoped to specific shops. That is deliberate. An owner or manager role with access to all shops can see across them.
"The trial balance does not balance." Stop and raise it with support before relying on the statements. Everything else reads from the same ledger.
Before contacting support
Note the exact wording of any message, the till and shop, the time, and the receipt or reference number. Most questions about a figure are answered by finding the transaction it came from.