Cannot Send Eth on Kovan Network

Whenever I go to send eth from my wallet to a smart contract that I need to fund on the Kovan testnet, the ‘next’ button greys out whenever I change the amount. It will let me click through if I leave the amount sent at the default 0 eth.

I was able to successfully send another coin from the same wallet to another smart contract on Kovan.

I tried a trick I’ve seen in other similar questions here and changed the dropdown to an alt coin before changing it back to eth, but this did not work.