Incorrect message display after submitting form

Hello,

I have a problem with displaying message after submiting form.

So, the main problem is that when You hit “submit” it really sumbmit everything and I get information where I want to… BUT, after hitting submit button it display information that “There was an error trying to send your message. Please try again later.”, but in real life it went good and i got everything what I want.

The problem is on client site, when client see this kind of feedback he try to submit it again so it is unnecessary, but he doesn’t know that he sent it already, because message after submitting is false. It should show “Thank you for your message. It has been sent.”. The only way I managed to change that is changing messages to correct one in place where it shouldn’t be (i placed “Thank you for your message. It has been sent.” in “Sender’s message failed to send”. But it shouldn’t work like that.

Please tell me what do you need to solve that problem ?
Here are proper messages i have in my form, and as I wrote, after proper sending form, it gives me bad message:
https://ibb.co/pvC1ybz

Thank you for your answers, If you need more information please give me feedback.