Low coolant – MKL

Hello, yesterday my V70 P26 (VFL from 2004, 2.5T with 209 hp) came back from the timing belt change and a few other repairs on the front axle and brake renewal… After a few kilometers of display “little coolant, safely stop”. Yesterday filled up accordingly and then drove in the sum of about 80 km. Today morning pure in’s car and same error message, coolant at minimum. 🙁 refilled but MKL remains on, no further information is visible in the display. I could not check whether coolers are leaking, as the parking area was all around wet due to permanent rain. Have autotechnically “2 left hands and only thumbs on it”, so I depend on the workshop.