What if all melodies have been sung before?

What if all melodies have been sung before?, this is a question that came to my mind since the year 2012 when we were composing songs with Compassion international Choir, Impuhwe choir and a Small Music band that I had created with my friends in Gisenyi Town, in the process of writing song lyrics, humming as we try to set it to a melody, I heard one of us saying "" guys that tune sounds familiar let's keep thinking in order to come up with a very new" melody that doesn't sound like any other existing song,  we had small debate about the idea some of us started humming familiar songs to prove the point,  so we agreed to keep looking for a very unique melody and finally settled on one so we proceeded and finished the song.

Here comes the Day to introduce the song to a the rest of the team members, with excitement we gave them printed lyrics, and I we sang for them the whole song first then before I started teaching the song, some choir members seemed un interested, when I asked Why?, they started saying that the song doesn't sound original that it's similar to particular songs and so on. 

Was it over analysing and over searching?.

When I was searching about a South African Artist The 👑 een of Gospel Rebecca Maloppe I came across her songs that sounded so similar with Some Rwandese and Tanzanian songs, such as the song Umoyawam

https://youtu.be/gafcHWepDPE?si=llo3YCDo8L79_btK

 which is very similar to Moyo wangu by Christina Shusho,  

https://youtu.be/-cNOSNUZtfQ?si=gHdKQXrSb4q71gx-

this made me think that Shusho was possibly influenced by Maloppe. I want to finish with a popular in Kenya Taunet Nelel by Emmy Kosgei  https://youtu.be/kxu0-Bn_Osg?si=s4T-9GaFQFYb0ayI which I find similar to the song Mugomboti by Brenda Fassi, 

is there songs that you find very similar in Rhythm and melody to? I'd love to hear from you in the Comment section.

please respond to the following questions as well:

do you find yourself getting a similar song pop up in your head while trying to create a new one or while listening to any song?

do you intentionally utilize popular tunes to blend with your composition?