Normally, if possible, I would download and check out the user manual for myself. Annoyingly, however, it seems that for this particular model I can find manuals in just about any European language apart, that is, from English.

So, without the aid of a safety net, I would hazard a guess that having tried both the original and universal, with the same result, the i.r. receiver circuit in the TV has developed a fault. Therefore, unless one is conversant with TV repairs, I believe a visit to Mr TV Repairman is likely to be required.