I have been trying to laser an order of Yeti tumblers on the roller rotary and Ortur Laser Master 2. The first couple runs came out good but after a few runs, the first letter of the text stopped printing. No matter what I do I cannot get the first letter to burn but the letters after look great. It sometimes prints as a single line but never finishes the whole letter.
Show us what you start with and what you are seeing as a result.