Can I make it so that each drop down option can only be used once on an input table?

Please can someone tell me how to set my input table so that each drop down option can only be used once?

Many thanks :)

I am not sure if I understand your query correctly. Do you mean to each user will be able to select the option from the dropdown for each submission while submitting the form? For example, it is not allowed to select the same option for the dropdowns in the same submission as in the image below:

Is that correct? If so, unfortunately, it is not possible with Input table field. However, you may use different individual dropdown fields and setup conditions to check duplicate selections and display a message. Please see the example below: 

Let us know if that works. Let us know if you are referring something different. We will be happy to help.

It looks like your response is not posted on the thread. Here it is for reference.

Thank you I have tried this, but it is showing 'drop off can only be used once' even if I only use it once. And I have definitely selected ALL rather than ANY for the conditions?

It seems that there is a conflict with the conditions. Please allow me some time to check on the conditions and get back to you with relevant information. 

Thank you for your patience. 

Thanks for being patient. I have checked the conditions for the field and see that a condition was set with the same rule. 

Please try changing the rule in the condition as shown below and it should be working fine.

Hope this information helps! 

That is what I had already done! Any other suggestions please?

I have checked the conditions on your JotForm and see that the specified condition is still displaying the same rule. 

However, I have made the necessary change to the condition on your form. The message is now displayed only when two Drop Off fields are selected. Please check and let us know if you need any further assistance.