Unsupported or invalid g-code command found in block

I have a problem that i can draw cut but as soon as i try a letter text or impoort svg, it comes on for a second and then it stops and has this error message Unsupported or invalid g-code command found in block. any help would be greatly apprecated I am using I draw machine with there laser head.

For one of the problem scenarios, can you go to File->Save gcode, then save the file with a .txt extension, then upload the file here. I’ll review to see if anything odd there.

I am not familiar with this. You indicate in your profile that you have a GRBL controller. Can you confirm that this laser you’re referring to here is indeed GRBL based?