Is Bowel Movement About 3-5 Times A Day Yellowish I Color A Sign Of Indigestion ?

Hi, Doctor! I would like to ask if it s indigestion my baby is suffering. She is having frequent bowel movement about 3 to 5 times or more in 24 hours. not watery though, just as thick as peanut butter, yellowish in color. it has been like this for months. is it because of allergy to formula milk? today, i had her water melon, after 3 hours, i saw in her stool undigested red bits of watermelon. i observed that it seems she isnt able to digest her foods, even milk. she lose some of it in her stool after few hours of intake she is 8 months old and i have been giving her solid foods since 4 months. she is losing weight. pls help me. she was born 1.9 kilos only doubled her weight after a month or 2, but now she just weighs 6.5 kls. is it normal?