Anet A8 heat bed won't heat past 25 degrees C

So for my first 3D printer I got the Anet A8 like severaly others the build went fine got it up and running printed a test file from the printer and it printed fine. After this I pulled the painters tape off and have put a Buildtak mat on the print bed I also downloaded Cura 2.6.2 and started getting things from thingiverse. I managed to print a few upgrade and not have any problems. Since I had the buildtak on my printer I didn't worry about heating the heat bed so I left that at 0 degrees and that worked for a few smaller prints but larger prints would not stick to the bed, so I raise the temp of the bed to 25 degrees C and it kinda worked for prints that were a little bigger but they had to have brims on them. After having about a 50/50 shot at having success I wanted to print something for a family member that was a bit larger. This time as soon as the print started the brim came off in a matter of 10 seconds so after trying about 3 times and it failing everytime I figure well peoples prints get stuck at 55 degrees C so I tried 40 degrees C but once I put my SD card back into the printer and selected the file it would show what temp the heat bed was at and what temp it needed to be but was holding a constant temp and wasn't rising, so I looked and the temp for the extruder was sitting at about 10 degrees C and it said the temp it needed to warm up to was 0 degrees C instead of the 190 degrees I had set in Cura. I think this is a problem with the files because older files when selected show the correct temp the bed and extruder need to get to and the printer does indeed gets to those temps and start to print it just seems to be newer files, the only time it will let me print now is if my bed temp is set to 25 degrees C. Can anyone help.