Your lines, drawings or whole layout are missing.
You are on a different layout, or not logged in to the same account.
Drawings belong to a saved layout, not to a symbol or to your account in general. A layout stores the charts, their indicators and the drawings on them as one object, and switching layout swaps the whole set. If you drew on a layout without saving, or you loaded a different layout afterwards, the drawings are not lost so much as attached to something you are no longer looking at.
Visibility settings add a second layer. Each drawing has its own rules about which timeframes and which symbols it appears on, so a line drawn on a daily chart can be set to show only on the daily and will be genuinely invisible on the hourly while still existing. That is why drawings appear to vanish when you change timeframe and reappear when you change back.
Load the layout by name from the layout menu and confirm the drawings are present, then change timeframe and back to see whether they persist. Checking the object tree for the chart shows what actually exists on it, which distinguishes a drawing that is hidden by its visibility settings from one that is genuinely not there.
Save the layout explicitly after significant work rather than relying on it being kept for you, and give layouts clear names so you can tell them apart. Set timeframe visibility deliberately when you draw a level you want to see everywhere. Make sure you are signed in before you start drawing, since work done signed out is not stored to your account.
Market Structure Pro gives one clear TRADE or NO-TRADE verdict on any MT5 chart, with confidence, grade and a plain-English reason. Free 7-day trial, no card.
Start free trial