if a device is responding a user defined VIF 0x7c (Plain Text) is not supported and causes all next records to be broken or causen an exception!
See https://m-bus.com/assets/downloads/MBDOC48.PDF page 42.

It can be reproduced with following device response:
"68 56 56 68 08 5F 72 91 91 01 19 77 04 14 16 A0 00 00 00 0C 78 91 91 01 19 0D 7C 08 44 49 20 2E 74 73 75 63 0A 20 20 20 20 20 20 20 20 20 20 04 6D 00 0C 8A 26 02 7C 09 65 6D 69 74 20 2E 74 61 62 4A 14 04 14 0D 7A 05 00 04 94 7F 00 00 00 00 44 14 57 B0 04 00 0F 00 01 1F 22 16"