Wont let me sell entire investment

What does this mean and why am i getting it? I just want to sell the entire stock when it reaches the set price?
Please help

Do you have another sell order for the same stock?

No that is the only one

Will you have a fraction left after you sell the 155? Have you tried to sell 154?

Yes it lets me do it aslong as i dont sell the entire investment. Then when it sells im left with 1 share

Are you sure you don’t have a fraction lying around somewhere? Possibly in a pie.

No its literally the only stock ive bought im just trying to set it to sell the whole investment

Try market sell of the remaining 1.

Yes that works but i just dont understand why its doing that